EMS Survivability Guidebook - DAU Sponsored...EMS Survivability Guidebook 7 1. Purpose The purpose of this guidebook is to assist Requirements Officers (ROs) material developers (MATDEVs)

UNCLASSIFIED

EMS Survivability Guidebook

1 March 2017

Prepared by the Joint Staff in collaboration with US Strategic Command

and the Defense Information Systems Agency

DISTRIBUTION STATEMENT A: APPROVED FOR PUBLIC RELEASE. DISTRIBUTION UNLIMITED


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Department of Defense Guidebook for Electromagnetic Spectrum Survivability. A component of the System Survivability Key Performance Parameter (SS KPP)

Prepared by the Joint Staff in collaboration with US Strategic Command and the Defense Information

Systems Agency

Citation of this work should appear as follows: Department of Defense Guidebook for Electromagnetic Spectrum Survivability, 1 March 2017 Washington, DC: Office of the Joint Staff J-8.

Point of Contact:

Joint Staff, Strategy, Capabilities and Analysis Branch J-8, Force Protection Division, DDFPCW JS Pentagon, The Pentagon, Room 1D958 Washington DC 20318-8000 (703) 693-7116 DSN: 223


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Contents Acknowledgment .......................................................................................................................................... 6

1. Purpose ................................................................................................................................................. 7

2. Applicability ........................................................................................................................................... 7

3. EMS Endorsement Requirements Overview .......................................................................................... 8

4. The EMS Survivability Key System Attributes ....................................................................................... 9

4.1. Spectrum Protection ............................................................................................................... 10

4.2. System Adaptability ................................................................................................................ 10

4.3. Spectrum Access Flexibility ..................................................................................................... 10

4.4. Spectrum Efficiency ................................................................................................................. 11

4.5. Multi-Functionality .................................................................................................................. 11

5. Compliance steps: ............................................................................................................................... 12

5.1. Step 1 –Determine Applicability ............................................................................................. 13

5.1.1. Non EMS Reliant systems .................................................................................................... 13

5.1.2. EMS Reliant systems ........................................................................................................... 13

5.1.3. Platforms and Systems of Systems (SoS). ........................................................................... 13

6.2. Step 2 – Assess the Threats ..................................................................................................... 14

5.3. Step 3 – Determine the risk category ..................................................................................... 16

5.3.1. Procedure ............................................................................................................................ 16

5.3.2. Mission Types ...................................................................................................................... 17

5.3.3. Threat Levels ....................................................................................................................... 17

5.3.4. Impact levels if system is frequently disrupted .................................................................. 17

5.3.5. EMS Risk Categories ............................................................................................................ 18

5.4. Step 4 – Complete the Scorecard ............................................................................................ 18

5.5. Step 5 – Develop Requirements for the KSAs ......................................................................... 19

5.6. Step 6 – Establish performance criteria .................................................................................. 20

6. Concept for an EMS Survivability Scorecard ....................................................................................... 22

7. Scorecard Evaluation Criteria .............................................................................................................. 22

7.1. Spectrum Protection ............................................................................................................... 22

7.1.1. Resilience ............................................................................................................................ 23

7.1.1.1. Passive Resilience ................................................................................................................ 23

7.1.1.1.1. Physical shielding ............................................................................................................ 24


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7.1.1.1.2. Noise Reduction .............................................................................................................. 25

7.1.1.1.3. Filtering ........................................................................................................................... 25

7.1.1.1.4. Signal amplification ......................................................................................................... 25

7.1.1.1.5. Error Detection and correction ....................................................................................... 25

7.1.1.2. Active Resilience ............................................................................................................. 26

7.1.1.2.1. Adaptive signal processing .............................................................................................. 26

7.1.1.2.2. Interference Cancellation ............................................................................................... 26

7.1.1.2.3. Spread-Spectrum & Wideband Technologies ................................................................. 27

7.1.1.2.4. Null steering/spatial nulling (Mechanical or electronic) ................................................. 27

7.1.1.3. Cooperative Resilience .................................................................................................... 28

7.1.1.3.1. Interference alignment (IA) ............................................................................................. 28

7.1.1.3.2. Cooperative Communications ......................................................................................... 28

7.1.1.3.3. Multi-Static Radar ........................................................................................................... 28

7.1.2. Graceful Degradation .......................................................................................................... 28

7.1.3. Wartime Reserve Modes (WARMs) .................................................................................... 29

7.1.4. Countermeasures ................................................................................................................ 30

7.1.4.1. Passive Countermeasures ............................................................................................... 30

7.1.4.1.1. Emissions control ............................................................................................................ 30

7.1.4.1.2. Stealth ............................................................................................................................. 30

7.1.4.1.3. Threat Detection & Warning ........................................................................................... 31

7.1.4.1.4. RF Decoys ........................................................................................................................ 31

7.1.4.1.5. Anti-jamming/Anti-spoofing ........................................................................................... 32

7.1.4.2. Active Countermeasures ................................................................................................. 32

7.1.4.2.1. Defensive Electronic Attack (DEA) .................................................................................. 32

7.1.4.2.2. Spoofing .......................................................................................................................... 33

1.3.2.2.1. Masking ........................................................................................................................... 33

1.3.2.2.2. Meaconing ...................................................................................................................... 33

7.1.5. Light Wave Threat Protection .......................................................................................... 34

7.1.5.1. Vulnerability Reduction................................................................................................... 34

7.1.5.2. Camouflage ..................................................................................................................... 34

7.1.5.3. Masking/Screening .......................................................................................................... 34


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7.1.5.4. Decoys ............................................................................................................................. 34

7.1.5.4.1. Flares ............................................................................................................................... 35

7.1.5.5. Dazzlers ........................................................................................................................... 35

7.1.6. Laser Protection .................................................................................................................. 36

7.1.6.1. Filters ............................................................................................................................... 36

7.1.6.2. Shutters ........................................................................................................................... 36

7.1.6.3. Anti-laser Aerosols .......................................................................................................... 36

7.1.6.4. Shielding .......................................................................................................................... 36

7.2. Radio Frequency (RF) Management........................................................................................ 37

7.2.1. Frequency Agility ................................................................................................................. 37

7.2.1.1. Frequency Tuning Range ................................................................................................. 37

7.2.1.2. Frequency Sharing ........................................................................................................... 38

7.2.2. Bandwidth Management .................................................................................................... 38

7.2.2.1. Variable Bandwidth Management .................................................................................. 38

7.2.1.2. Unintentional Emissions Control .................................................................................... 38

7.2.3. Modulation Management ................................................................................................... 38

7.2.3.1. Adaptive Modulation ...................................................................................................... 39

7.3.1.1.1. Adaptation Speed............................................................................................................ 39

7.3.1.1.2. Non‐Contiguous Bandwidth Use (Carrier Aggregation) .................................................. 39

7.2.4. Power Management ........................................................................................................... 40

7.2.5. Antenna Management ........................................................................................................ 40

7.2.5.1. Adaptive Antennas Systems (Directional Antennas) ...................................................... 40

7.2.5.2. Multi‐Path Effects Awareness ......................................................................................... 41

7.2.5.3. Multi-functional Antennas .............................................................................................. 41

7.3. Geographical Awareness ....................................................................................................... 41

7.3.1. Location Awareness ............................................................................................................ 41

7.3.2. Orientation Awareness ....................................................................................................... 41

7.3.3. Location Information Exchange .......................................................................................... 42

7.4. Electromagnetic Environmental Awareness .............................................................................. 42

7.4.1. Environmental Sensing........................................................................................................ 42

7.4.1.1. Limited Frequency Sensing ............................................................................................. 42


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7.4.1.2. Full Range Frequency Sensing ......................................................................................... 43

7.4.1.3. Basic Environmental Categorization ............................................................................... 43

7.4.1.4. Enhanced Environmental Categorization ....................................................................... 43

7.4.2. Environmental Information Exchange ................................................................................ 43

7.5. State Management .................................................................................................................. 43

7.5.1. Function/State Awareness .................................................................................................. 44

7.5.2. Automated Function Control .............................................................................................. 44

7.5.2.1. Adaptive Control ............................................................................................................. 44

7.5.2.2. Cognitive Control ............................................................................................................ 44

7.5.2.3. Intelligent Control ........................................................................................................... 45

7.5.3. Function/State Data Exchange & Reporting ....................................................................... 45

7.6. Network Management ............................................................................................................ 45

7.6.1. Network Overhead Reduction ............................................................................................ 45

7.6.1.1. Collision Management .................................................................................................... 45

7.6.1.2. Transport Control ............................................................................................................ 46

7.6.2. Topology Management ....................................................................................................... 46

7.6.2.1. Network Routing ............................................................................................................. 46

7.6.2.2. Directional Routing ......................................................................................................... 46

7.6.3. Access Priority ..................................................................................................................... 46

7.6.4. Quality of Service ................................................................................................................ 47

7.6.5. Link Monitoring ................................................................................................................... 47

7.6.6. Spectrum Management Integration ................................................................................... 47

7.7. Data Management ................................................................................................................. 47

7.7.1. Filtering ............................................................................................................................... 47

7.7.2. Onboard processing ............................................................................................................ 48

7.7.3. Data Throttling .................................................................................................................... 48

7.7.2. Data Compression ............................................................................................................... 48

7.7.3. Encryption ........................................................................................................................... 48

7.7.4. Data Error Detection & Correction ..................................................................................... 48

7.7.5. Data Recording .................................................................................................................... 49

Appendix A - Guidance for endorsement reviewers............................................................................... 50


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Appendix B –Completing the EMS Endorsement Scorecard................................................................... 52

Appendix D - Prescribed Performance Criteria ....................................................................................... 53

Appendix E – Sample Requirements Statements ................................................................................... 65

Appendix F – Best Practices for Compliance ........................................................................................... 73

Appendix G – Acronyms .......................................................................................................................... 75

Appendix H – Glossary ............................................................................................................................ 78

Tables Table 1 - Suggested Performance Criteria .................................................................................................. 55 Table 2 - Sample High-Level Operational Requirements for ICD .…………………………………………………………..66 Table 3 - Sample Requirements Statements…………………………………………………………………………………………..67

Figures

Figure 1 - Applicability of the five EMS Endorsement KSAs .......................................................................... 8

Figure 2 - Basic Compliance Steps ............................................................................................................... 12

Figure 3 - EMS Risk Category Determination Process ................................................................................. 16

Figure 4 - Summary of required document elements for EMS Endorsement ............................................ 21

Figure 5 - Compliance steps throughout the JCIDS process ....................................................................... 21

Acknowledgment This guidebook was developed by the EMS Survivability Guidebook working group which was chartered

by the Joint Staff, J-8 and the Protection FCB.

The primary author of this guidebook is Mr. Bill Lussier of the Defense Spectrum Organization.

The majority of the ideas on spectrum efficiency criteria discussed in section 7 come from Mr. Mike

O’Hehir’s “DoD Electromagnetic Strategy, Spectrum Best Practices” draft concept paper from Dec 2012.


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1. Purpose The purpose of this guidebook is to assist Requirements Officers (ROs) material developers (MATDEVs)

and Program Managers (PM) in complying with the requirements of Electromagnetic Spectrum (EMS)

Survivability as addressed within the System Survivability KPP. This guidebook is intended for DoD

personnel responsible for requirements generation and acquisition life cycle processes, including test

and evaluation of systems that might be susceptible to effects from the Electromagnetic Operating

Environment (EMOE).

The purpose of the EMS Survivability is twofold. The first is to ensure proper consideration of EMS

threats, vulnerabilities and potential electromagnetic operational environments (EMOE) in which their

systems/equipment are intended to operate prior to making design decisions and specifying system

survivability requirements. Only by understanding the risks of the intended EMOE can PMs and

MATDEVs adequately appreciate any requirements for survivability features in their designs. The

second is to ensure that the broad gamut of EMS Survivability related issues are properly addressed

during the requirements development process. These goals will be achieved through proper threat and

risk assessments and by complying with the requirements of the spectrum Key System Attributes (KSA).

2. Applicability

The EMS Survivability portion of the SS KPP applies to all systems that incorporate electrical or electronic

components which might be susceptible to electromagnetic effects but its scope differs substantially

depending upon the type of system. While designed specifically for systems with joint equity going

through the JCIDS process, Service developed systems will benefit from applying the same approach to

developing EMS Survivability requirements.

2.1. All systems, including platforms and Systems of Systems (SoS), that might be vulnerable to an

adversary’s employment of the EMS (From Extremely Low Frequencies (ELF) or 3 Hz to the

upper limit of Ultra Violet (UV) light at 30 PHz) must comply with the Spectrum Protection (SP)

KSA and must include EMS threat analyses in the system threat assessment already required by

DoDI 5000.2 and the Intelligence Certification (if one is required). The results must be

documented in the System Threat Assessment Report (STAR).

2.1.1. EMS threat assessments are not required for systems designed to operate solely in

domestic garrison or non-threat environments.

2.2. Spectrum-Dependent Systems (SDS) must comply with all five of the EMS Survivability KSAs and

an EMS threat analysis. For the purposes of EMS Survivability, SDS are systems that operate

only in the radio frequency (RF) portion of the spectrum (3 KHz to 275 GHz). SDS are defined as

those electronic systems, subsystems, devices and/or equipment that depend on the use of the

RF portion of the electromagnetic spectrum to operate. SDS may use spectrum for

transmission or reception of information, for surveillance and warning, for intelligence

gathering, measurement, navigation, positioning, and timing. Another subset of SDS are those

that employ electromagnetic energy to deny others the ability to use spectrum.


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2.3. For systems that do not operate in the RF portion of the spectrum, the four additional KSAs do

not apply.

2.4. The EMS Survivability process is designed to be complimentary and not duplicative of existing

spectrum related requirements (e.g., Certification). It in no way absolves program offices from

complying with these. Where it overlaps with them, it defers to their requirements and not the

other way around. Expressed more succinctly, in addition to obtaining endorsement for EMS

Survivability, SDS must still comply with all applicable spectrum certification, supportability and

E3/EMC direction.

Figure 1 - Applicability of the five EMS Survivability KSAs

3. EMS Survivability Requirements Overview The chairman of the Joint Chiefs of Staff has charged the Protection Functional Control Board (P-FCB)

with the responsibility to develop and oversee administration of the System Survivability Key

Performance Parameter (SS KPP). Recognizing that System Survivability has several important aspects

that all contribute to the overall survivability of a system, the protection FCB has deliberately divided the

topic into three components: Kinetic, Cyber & EMS. Doing so allows a separate spotlight to be shined on

each of these key aspects. These aspects fully support the overall objectives of the SS KPP, namely to

promote system development that:

- Prevent kinetic or non-kinetic attacks

- Mitigates negative effects of any kinetic or non-kinetic attacks

- Promotes recovery of the system’s capabilities after an attack

EMS Survivability is intentionally interpreted to be broad in scope. It applies to all systems, including

platforms and Systems of Systems (SoS), that might be vulnerable to an adversary’s employment of the

entire EMS. This will help ensure that ROs/PMs/MATDEVs factor in survivability features for the many


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types of non-kinetic, EMS threats (e.g., Directed Energy (DE) weapons, Infra-red (IR) seekers, lasers and

Ultra-Violet (UV) detectors) and not just resilience to RF jamming by an adversary.

This guidebook focuses more attention on the early stages of requirements and system development.

By shifting the timeline a little to the left, it is intended that EMS considerations will not be applied too

late to effect key design milestones or so late that they are prohibitively expensive to implement.

The process for gaining endorsement employs an online, EMS Survivability Scorecard to help

ROs/PMs/MATDEVs assess the types of technologies, techniques and design features that are available

to address the specific types of threats a system may encounter. This Scorecard also helps to evaluate

compliance with the EMS KSAs. The Scorecard consists of a progressive series of questions that the

RO/PM/MATDEV answers online during each stage of requirements development. The questions are

appropriate to the stage of development and category of system, lead the developer to understand the

many design vs risk tradeoffs and to consider various components, technologies and techniques which

can effectively address the five KSAs.

EMS Survivability focuses on five key attributes that all contribute to producing a highly survivable

design. These attributes are Spectrum Protection, System Adaptability, Spectrum Efficiency, Spectrum

Access Flexibility and Multi-functionality. Employed together these design attributes will not only

improve survivability but will enable far more agile and effective capabilities for our fighting forces.

This piece of the SS KPP is also designed to be easier to review and enforce. It mandates that specific

information be included in each JCIDS specified milestone document so that reviewers can more readily

assess whether or not the system includes adequate requirements and design features to survive EMS

threats. This guidebook also provides guidance to improve the review process (See Appendix A).

Most of the mandatory KPPs are constructed to require programs to establish measurable and testable

performance criteria. While this EMS survivability process includes performance criteria, it also focuses

on other factors that promote spectrum survivability in both congested and contested environments. It

mandates that ROs/PMs/MATDEVs closely study the predicted EMS threats their systems will face and

establish a realistic level of risk that then must be managed like any other type of risk.

More uniquely, this guidebook provides three features not found elsewhere: 1) a detailed list of

technologies, techniques and features that the Requirements Officer or system designer can and should

use to develop specific system design requirements. 2) a list of standardized, pre-vetted performance

criteria to choose from and which reflect the prescribed design attributes, 3) a list of sample

requirements statements that can be used to inspire and inform the final design requirements for a

system. This more comprehensive approach should result in a more survivable system.

4. The EMS Survivability Key System Attributes Producing a system design that will be survivable against various EMS threats is a multi-faceted task. No

single technology, component or procedure can mitigate the wide variety of risks and threats that might

be encountered in an operating environment. Consequently EMS Survivability focuses on five key


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attributes that all contribute to producing a highly survivable design. While these five are not always

equally important to a particular design or to all operating environments, if the designer applies proper

consideration to each of them, most potential threats can be at least mitigated if not eliminated. In high

threat environments and scenarios, survivability demands the incorporation of every one of the

attributes. In low threat environments survivability may only require that some basic electronic

protection design features be employed. The stakeholders for any particular system must weigh the

costs and benefits of each KSA against the predicted threats and choose an appropriate balance or mix

of technologies/components etc. that will be specified in the system’s requirements.

4.1. Spectrum Protection (SP) is a hybrid term that combines those aspects of Electronic

Protection, Electronic Support and Electronic Attack that contribute to system survivability

against EMS threats. It involves actions taken to protect equipment from any effects of

friendly, neutral or enemy use of the electromagnetic spectrum (From Extremely Low

Frequencies to UV light waves or 3 KHz to 30 PHz) that expose, degrade, neutralize, or destroy

friendly combat capability. It broadly includes things like physical durability, deception, counter

measures, component resilience, security from compromise and redundancy. SP is the most

obvious of the EMS attributes and includes the types of considerations most would consider to

be important for system survivability from an EMS perspective.

4.2. System Adaptability is defined as the ability of a system to maintain awareness of its current

state of operation and to automatically adjust multiple operating parameters in order to

optimize performance, execute required functions, to counter threats or accomplish assigned

missions.1 This has implications and applications that go way beyond the use of the spectrum.

In particular it enables systems to adjust operating parameters at the pace that threats actually

present themselves, which can often be in milliseconds. The benefits of well-designed,

adaptable SDS will be that they are operationally adaptable as well. Unfortunately most legacy

SDS are not particularly adaptable. A significant percentage of today’s SDS must be manually

tuned and adjusted. Decisions to employ particular modes, frequencies, functions,

countermeasures and operating parameters are controlled solely by the operator. Such

designs necessitate that we employ the spectrum in a ponderously slow and predictable

manner, squander spectrum resources and render our systems vulnerable. Unfortunately, this

distinctly non-dynamic status quo will not support the fast paced and dynamic reality of

modern spectrum operations. More cognitive and adaptable SDS are required to enable agile

spectrum operations of the future. Systems that recognize their own state and immediately

adjust a variety of operating parameters to ensure mission accomplishment are not only more

survivable but will be essential to achieving EMS superiority in the operational environment.

4.3. Spectrum Access Flexibility is defined as the capability of a Spectrum Dependent System

(SDS) to exploit multiple opportunities to access spectrum (e.g., multi-band operation, sharing

spectrum with other systems, wide tuning ranges).2 Systems that can access the spectrum

1 DoD Electromagnetic Spectrum Strategy, Sep 2013 2 Ibid


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flexibly will be critical for relieving spectrum congestion and improving operational

effectiveness; particularly in the lower RF ranges below 6 GHz that are so desirable. Such

flexibility also provides inherent survivability in a contested battlespace. Most current SDS are

designed (essentially hard-wired) to operate in narrow, fixed frequency ranges. This legacy

design convention causes three significant problems: 1) Lack of worldwide supportability - Since

the regulatory band assignments are not the same worldwide, SDS that are legal to operate in

North America may not be legal in Europe or the far-east and vice-versa. This sometimes

causes challenges for DoD systems that need to operate worldwide and has caused

oversubscription in those few bands that are available worldwide. 2) Operational vulnerability -

These fixed bands are well known throughout the world so it is no major feat of intelligence or

engineering for adversaries to effectively target our SDS. 3) Reduced effectiveness -When

operations in a certain frequency band suffer from interference, SDS that are hard-wired for

that narrow frequency range cannot simply shift to a better frequency but must resort to other

(often less effective) countermeasures to mitigate the interference. Often little or nothing can

be done to mitigate the problem resulting in mission degradation or failure. However, SDS

that are designed with wide tuning ranges, to operate in multiple frequency bands or that can

share spectrum with other users can effectively mitigate all three of these problems.

4.4. Spectrum Efficiency is defined in two equally important ways. a) The minimum use of EMS

resources (frequency, time, energy, and space) necessary to ensure operational effectiveness in

fully accomplishing the required mission. b) A relative measure to compare SDS when one

achieves the same mission objective using fewer spectrum resources, taking into account one

or more of the dimensions of frequency, time, energy, and physical space (longitude, latitude,

and altitude).3 Efficiency effects survivability for two reasons: 1) Much of the RF spectrum,

particularly below 6GHz, is oversubscribed and congested. The DoD regularly experiences cases

of SDS being denied frequency assignments because of oversubscription and there are many,

many instances of frequency fratricide that is just one common symptom of such congestion. If

the DoD does not start fielding SDS that use the EMS more efficiently then this problem will

continue to grow. It is truly an operational imperative that we use the spectrum more

efficiently. 2) Many of the technologies/techniques, etc. that will produce more spectrally

efficient designs will directly reduce vulnerability. Think how much more difficult it is to detect

a system that uses an adaptable, multi-directional antenna or that can modulate its power

output to the lowest level necessary to maintain effectiveness. High efficiency designs are just

much less vulnerable. This is why it is included as a KSA.

4.5. Multi-Functionality is the ability of a SDS to perform multiple missions and functions.4 The

proliferation of all types of devices in the modern battlespace has brought tremendous

capability but at a significant cost in terms of space, weight, power, logistics, maintenance and

even training burden. Modern software driven devices like software defined radios and RADARs

can often be programmed to perform multiple functions and missions. This fact should be

3 DoD EMS Strategy Roadmap & Action Plan, Sept. 2015 4 ibid


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leveraged to mitigate the previously mentioned negative consequences whenever practical.

Even in cases where a secondary function does not truly replace a primary piece of equipment,

it can serve as a backup or redundant capability. These factors directly support system

survivability as well as mission accomplishment. This attribute leverages the previous ones in

that SDS that are adaptable, flexible and efficient can often be modified or programmed to

perform multiple functions. Whenever practical, SDS should be designed to accomplish multiple

missions and functions thereby reducing the overall footprint, weight, power and complexity of

the equipment our forces must employ in the battlespace and thereby decrease their

accompanying logistics tail, training burden and vulnerability. This multi-functionality attribute

is intended to help developers to consider these factors when designing their SDS.

5. Compliance steps: The early stages of requirements development are the most influential in system design. Many critical

design decisions are difficult or expensive to change the closer to production and deployment a system

gets. Therefore it behooves the RO/PM/MATDEVs to devote adequate consideration to EMS

survivability issues before requirements are finalized. Later stages should be evaluated as well so that

the endorsement review can take into account any trade-offs or design changes that occur later in the

development process. In fact, consideration of applicable EMS KSAs should be made during every stage

of the acquisition cycle. The steps laid out in this section will specify how to conduct and document

these considerations in the appropriate sections of each capability requirements document.

While the SS KPP focuses on the JCIDS milestone documents (i.e., ICD, CDD, CPD, and IS versions of

these), program offices and sponsors are encouraged to inject EMS considerations and requirements

into other key acquisition documents like the Information Support Plan (ISP), Analysis of Alternatives

(AoA), Acquisition Strategy (AS), System Engineering Plan (SEP), Test & Evaluation Master Plan (TEMP)

and Request for Proposals (RFP). This will help ensure that the end solution has incorporated all of the

extensive forethought and planning that goes into the key requirements documents.

Figure 2 - Basic Compliance Steps


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5.1. Step 1 –Determine Applicability

5.1.1. Non EMS Reliant systems

If the system has no reliance on the EMS (does not INTEND to emit or receive

electromagnetic energy as part of is function) but has electronics or electrical

components that are susceptible to the effects of the EMS (almost all do) then much of

this process will not apply. The only requirement is to follow existing guidance outlined

in DoDD 3222.3 which describes the DoD’s E3/EMC program and requires program

offices to address E3/EMS requirements during the acquisition process. If the system

falls into this category then insert the following language into the EMS Survivability

section of each prescribed capability requirements document:

“This system is not EMS reliant but contains components that are potentially

susceptible to the negative effects from the EMS. See the Spectrum Requirements section

for coverage of E3/EMC requirements.”

5.1.2. EMS Reliant systems

If the system must emit or receive electromagnetic energy to perform its functions then

it is reliant on the EMS (Defined as extending from Extremely Low Frequencies (ELF) or 3

Hz to the upper limit of Ultra Violet (UV) light at 30 PHz) and must comply with all

portions of the process. All such systems must complete steps two through five below.

5.1.3. Platforms and Systems of Systems (SoS).

Many systems are more accurately described as platforms or systems-of-systems (e.g.

Ships, Planes, Vehicles, etc.) which may incorporate one or more EMS reliant

subsystems. Platforms or SoS also need to complete all portions of the process but

need only apply the SP KSA when completing steps four and five. In addition

ROs/MATDEVs/PMs developing requirements for platforms and SoS must:

Consider the overall levels of spectrum protection that will be required to effectively

execute all potential missions. Requirements for hosted SDS should also be

developed that can contribute to the entire platform’s desired levels of spectrum

protection. Once the most challenging EMOE in which the platform might operate

has been identified, all hosted SDS must be reviewed to ensure that they can

operate effectively in this EMOE or that there are requirements/measures identified

to mitigate any loss of mission performance.

Verify that the various EMS reliant systems to be hosted on the platform or SoS

have received or have applied for a SS KPP endorsement to the SS KPP. One method

to accomplish this is to check the Joint Staff KM/DS archive. (Only applicable for

hosted ones that have begun the JCIDS process after Jan 2018). This verification can

be commenced at any point but should be completed and summarized in the SS KPP


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section of the CPD. If an EMS reliant subsystem was developed prior to January

2018 or did not go through the JCIDS review process then just state so in this

summary.

If a hosted SDS system has not yet been issued a SS KPP endorsement for EMS

Survivability this fact should be noted in the CPD summary. If the hosted SDS was

denied an endorsement for EMS Survivability, then the reason for the denial should

be noted and any measures that must be employed to mitigate the noted deficiency

shall be noted as well.

If the hosted SDS is based on a commercial system, it will not have an SS KPP

endorsement to review. These systems may have other accreditations or be

compliant with National Institute of Standards and Technology (NIST) and/or

Institute of Electrical & Electronics Engineers (IEEE) standards. However, such

credentials do not guarantee adequate levels of resilience in the predicted threat

environments or even electromagnetic compatibility with other hosted systems.

Use of commercial SDS makes compliance with E3 and EMC testing requirements

(see below) even more critical. Use of these types of subsystems shall also be noted

in the CPD summary.

5.2. Step 2 – Assess the Threats

Include EMS threats in the System Threat Assessment as required by DoDI 5000.2 and by the

Intelligence Certification in the JCIDS Manual. Threat assessments shall be used to inform system

requirements and design trade-offs. They shall also be used to inform the Program Protection Plan

(PPP) and other MS documentation as appropriate. Service intelligence commands produce these

assessments for most developmental programs and they are documented in a System Threat

Analysis Report (STAR). Provide a link to this report in each JCIDS prescribed capability

requirements document for review or attach a copy.

5.2.1. At the beginning of the Material Solution Analysis phase, the program office or

capability sponsor should contact the appropriate intelligence production center (Each

Service has one) to support integration of validated threat information into the

Technology Development Strategy. Usually a Threat Steering Group (TSG) will be stood

up to oversee the development, production and updating of the STAR. It is critical that

the program office takes a proactive role in this working group. Close coordination from

the program office will help ensure that the threat analysis is sufficiently detailed and

comprehensive enough to accurately effect requirements development and design

decisions. As development progresses, the TSG must be kept apprised of any significant

changes to the system’s requirements and/or design so that the threat analysis can be

adjusted and updated correctly. When collaborating on the content and focus areas of

the STAR, the program office shall specifically request that the following topics to be

assessed:


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a. The capacity and technical ability of likely adversaries to deny, degrade and/or

disrupt the effectiveness (via jamming, deception, etc.) of the EMS reliant

system/SoS/platform being developed.

Note: If jamming is anticipated then the maximum field strength levels for such

jamming in the applicable frequency range(s) should be defined as part of this

assessment. Such data will be necessary for D/OT&E of the system.

b. The capacity and technical ability of likely adversaries to detect, surveil, classify and

target the types of emissions the system/SoS/platform will likely produce.

c. The ability and sophistication of likely adversaries to effectively employ Electronic

Warfare (EP, ES and EA) against the system/SoS/platform being developed.

d. The likely adversaries’ ability to effectively protect its own systems against attacks

from the system/SoS/platform to be developed. (Only applicable if the system has

an EA function).

If desired the program office or capability sponsor may request an initial threat analysis

for these specific topics be conducted in advance of the MS “A” STAR. Similarly, an

interim report may be requested between milestones to cover specific topics such as

these.

The quality of analysis will in-part, depend upon how much supporting detail the

program offices can provide with the requests. In addition to previously produced JCIDS

documentation (e.g., an ICD) program offices should be prepared to provide the most

likely scenarios that the system will perform in (possible source is a CONOPS); a list of

which regions (or countries if possible) that the system will be deployed to; and the

likely frequency ranges that are contemplated for the system.

Guidance for conducting proper threat assessments can be found Section 8 of the

Defense Acquisition Guide (https://acc.dau.mil/CommunityBrowser.aspx?id=510535).

5.2.2. For systems (or platform/SoS) operating in the RF portion of the spectrum, determine

the intended EMOE in which the system will operate. This is a combination of the threat

data developed above and data on friendly and neutral systems which is developed for the

separately required Spectrum Supportability Risk Analysis (SSRA) (For more information

see DoDI 4650.3). These analyses are highly complementary so conducting these two

processes together or at least in parallel will help uncover the full range of “threats” a

system may encounter and will best determine the most challenging EMOE that the

system can be expected to operate in. Results should be summarized in the SSRA as well as

the STAR. Guidance for conducting an SSRA and determining the EMOE can be found in

References DoDI 4650 (https://acc.dau.mil/CommunityBrowser.aspx?id=154756&lang=en-

US ) and MIL-HDBK-235-1C including its supplemental parts.

(https://acc.dau.mil/CommunityBrowser.aspx?id=131912&lang=en-US )

https://acc.dau.mil/CommunityBrowser.aspx?id=154756&lang=en-US




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5.3. Step 3 – Determine the risk category

The EMS Survivability risk category is developed to assist in determining how much investment in

time and resources are warranted for EMS protection and mitigation features. The category is

determined by evaluating three contributing factors (The Mission Type, Threat Level and Impact

Level) and then deriving an overall risk level from them. It is not intended to be overly complicated

or sophisticated but the process should yield a clear indication of how much emphasis is required on

EMS protection and mitigation. Correspondingly, the determined risk category will also drive how

much of this emphasis should be reflected in the prescribed JCIDS documents. For example, if the

risk is determined to be high there will be an expectation that much more extensive and detailed

requirements be specified for EMS protection and mitigation. There will also be an expectation for

higher scores on the EMS Survivability Scorecard to reflect this concern to mitigate risk. It is

understood that the initial risk category determined for the ICD will be based on assumptions and

incomplete data. It is expected that the risk category may change as improved and more detailed

information is incorporated.

The determined EMS Risk Category shall be entered into the EMS Survivability section of the SS KPP

for each specified capability requirements document. Include a short description of why a particular

level was chosen.

Figure 3 - EMS Risk Category Determination Process

5.3.1. Procedure

1. Select the mission type first, then determine the threat level and impact level.

2. Weigh the three factors to then determine an overall risk category.


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- This requires a subjective value judgement. There is no prescribed formula or

weighting for this determination. However, all three factors must be considered.

- Some systems will intuitively fit into particular risk level; others may require

additional analysis and debate.

5.3.2. Mission Types

Strategic/National – Systems that primarily support missions of strategic or national

interest (e.g., National intelligence collection & dissemination, nuclear C2, Comms for

senior Defense Department leadership, etc.)

Operational/Tactical – Principal warfighting systems used to support or engage in

military operations (e.g., Airborne UHF, Counter fire radar, Tactical Data Links, etc.)

Support or non-warfighting – Systems that primarily support peacetime or military

support missions (e.g., range telemetry, domestic air traffic control, training

coordination, base security monitoring, etc.).

5.3.3. Threat Levels

High – Characterized by peer or near-pear adversaries who have the technical

capabilities and skill levels to; employ high-powered mobile, or airborne, jamming

systems; use agile or sophisticated jamming techniques (e.g., DRFM), employ Directed

Energy (DE) weapons, etc. Modest to advanced ES capabilities to surveille, classify and

target a wide range of allied SDS. For permissive EMOEs, the threats would be severe

restrictions, heavy congestion and/or likely interference within the designated

frequency bands.

Medium – Characterized by adversary with the technical capability to employ low or

medium-power fixed jammers, unsophisticated "white noise" or blanking EA techniques.

Basic to modest levels of skill in EA employment. Basic ES capabilities for detection &

tracking. Rudimentary capability to classify. For permissive EMOEs, the threats would be

in the form of mild restrictions, moderate congestions and/or occasional interference in

the designated frequency bands.

Low – Characterized by generally unsophisticated adversaries. Adversary may have

access to COTS or externally supplied EA equipment of relatively low power. Only basic

levels of skill in employing EA. Little or no ES ability to surveille or classify targets. For

permissive EMOEs, there would be few if any restrictions on emissions, low congestion,

and infrequency instances of interference in the designated frequency bands or perhaps

more frequent interference from long-standing and predictable sources.

5.3.4. Impact levels if system is frequently disrupted

Severe – Unacceptable loss of mission capability and war fighting capacity. Represents

loss of a critical tool for achieving success. Would typically result in a “no-go” or mission


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scrub decision. May result in loss of life or materiel. Represents a high value

warfighting system requiring much greater investment in protective measures.

Moderate - A partial or at least manageable loss of mission capability and/or war

fighting capacity. Redundant capability is available or work around(s) exists to continue

the mission. Would typically result in a mission delay or diversion. May contribute to a

loss of life or materiel. Represents a warfighting system which requires at least a modest

investment in protective measures.

Low – Partial and temporary loss of mission capability but not warfighting capacity.

Would typically only contribute towards a mission delay or diversion. Would not be

expected to contribute to a loss of life or materiel. Perhaps a secondary or redundant

capability but more likely a support or non-warfighting system for which the primary

impact would be financial or schedule and which may only require basic protective

measures.

5.3.5. EMS Risk Categories

High – System poses a severe risk to the mission if disrupted. Demands that more

extensive requirements for risk mitigation be imposed. Warrants a significant

investment in protection from EMS threats.

Medium – System poses a moderate risk to the mission if disrupted. Indicates that

threats should be prioritized and at least high priority threats will drive specified

requirements Warrants at least a modest investment in protection from EMS threats.

Low – System poses a low risk to the overall mission if disrupted. At least the mandatory

and customary requirements for risk mitigation shall be imposed. As long as these

minimum requirements are met, further investments may be weighed against other

program requirements.

5.4. Step 4 – Complete the Scorecard

Complete the EMS Survivability Scorecard during each phase of development. This will save

significant time and effort in completing the EMS Survivability requirements as it will obviate the

need to devote many paragraphs of explanation and justification for each KSA in the applicable

section of the acquisition requirements document.

5.4.1. The EMS Survivability Scorecard is the preferred method of evaluating compliance with

the EMS KSAs. The Scorecard consists of a progressive series of questions that the

RO/PM/MATDEV answers online during each stage of requirements development. The

questions are appropriate to the stage of development and category of system and lead

the developer to understand the many design vs risk tradeoffs and to consider various

components, technologies and techniques which will address the five KSAs. Questions

prior to MS A are rather general but get progressively more technically detailed by MS C.


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Scores are provided for each of the applicable KSAs. A preliminary set of scores is

automatically provided upon answering all questions for each phase. Final scores are

provided upon completion of the CPD series questions. These scores must be entered in

the EMS Survivability section of applicable JCIDS prescribed capability requirements

document for the endorsement team’s review. The complete scorecard with answers

shall be attached to the document as well.

The EMS Survivability Scorecard is an online survey tool that can be found on

SIPRNet at: ? and on NIPRNet at: ?

5.4.2. EMS Survivability includes five Key Systems Attributes (KSAs). The Spectrum Protection

KSA is the broadest in scope and applies to all EMS reliant systems applying for SS KPP

endorsement. The four additional KSAs (Spectrum Access Flexibility, Spectrum

Efficiency, System Adaptability, Multi-Functionality) apply to only those EMS reliant

systems built to utilize the RF portion of the spectrum and not just exist within it (for the

purposes of EMS Survivability the RF frequency bands extend from Very Low to

Millimeter Wave or 10 KHz to 100 GHz). The scorecard accounts for the type of system

and will only ask applicable questions for applicable KSAs.

Even beyond this basic division in applicability, not all spectrum KSAs will apply to all

SDS in all cases. (e.g., questions of spectrum efficiency have little applicability for a

radar altimeter that already uses such a small amount of bandwidth). System

developers and their Operational Sponsors should determine if a particular KSA

should not apply. If this is the case then a note must be made in the EMS

Survivability section of each JCIDS prescribed capability requirements document as

to why the KSA should not apply. This will alert the certifier and MDA to review this

reasoning and decide whether to grant the waiver. The Scorecard survey tool will

also help answer this question by progressively asking targeted questions that will

narrow the applicability or each KSA.

For a more in-depth discussion of the scorecard see Appendix B.

5.5. Step 5 – Develop Requirements for the KSAs

Develop requirements based upon the EMS KSAs and factoring in the determined Risk Category.

Refine and add to them for each subsequent phase of development.

5.5.1. ROs/MATDEVs/PMs shall specify system requirements for each of these KSAs unless the

key stakeholders (Operational Sponsor, Program Office, etc.) deem a particular KSA as

inapplicable. Use the scorecard and the information provided in Section 7 of this

guidebook to develop a list of specific EMS survivability related requirements that are

appropriate to each particular system. These should be listed in the EMS Survivability

section of each applicable JCIDS prescribed capability requirements document.

1.1.1.1. When developing EMS Survivability system requirements, the system’s function,

its intended operational environment and how critical it is to the intended mission


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should be taken into account. Not all systems need to be exquisitely adaptable,

flexible, resilient, etc. to effectively perform their intended mission.

1.1.1.2. It is natural and expected that this list will be expanded and refined as the

systems progresses through the JCIDS process.

1.1.1.3. Appendix D of this guidebook is a list of sample requirements statements that

are paired with the scorecard criteria detailed in Section 7. These should be used to

help define this more detailed set of EMS Survivability requirements.

5.6. Step 6 – Establish performance criteria

Determine if the Operational Sponsor or MDA requires performance criteria to be developed for any

of the applicable KSAs. If so, establish performance criteria with appropriate threshold and objective

measures. A RO or PM may also elect to establish performance criteria for one or more of the KSAs.

The inclusion of performance criteria serve to bolster the case for endorsement and provide testable

and measurable criteria for testing and evaluation. However, establishing appropriate performance

criteria is challenging for some systems and some KSAs. If EMS related performance criteria are

NOT required then note this in the CDD, CPD and TEMP and provide justification/reasoning why.

5.6.1. If performance criteria are required, then appendix D of this guidebook should be

consulted first for examples of acceptable performance criteria to adequately measure a

KSA’s performance metric. These prescribed performance criteria have been

developed and vetted for applicability and viability and may save the program offices

significant time in the long run. Document chosen performance criteria in the EMS

Survivability section of applicable JCIDS prescribed document.

Frequently, the system’s operational sponsor or MDA may prescribe the

development of threshold and objective performance criteria for one or more of the

EMS KSAs. In most cases it is best to use one of the prescribed criteria defined in

appendix 5 of this guidebook. These prescribed criteria have been developed to

adequately measure valid EMS KSA performance metrics. However, prescribed

criteria do not exist for all cases or all KSA’s so ROs/PMs may need to develop

unique ones to serve their purposes. Obtaining final SS KPP endorsement is not

contingent upon successful achievement of threshold scores for EMS KSA criteria.

Any performance criteria as well as MOEs and MOPs should be developed by a

program’s Test & Evaluation Integrated Product Team (T&E IPT). This team is made

up of stakeholder SMEs and a representative from the appropriate Service or Joint

T&E organization. 5 It can best ensure that any chosen performance criteria serve

their intended purpose and fit well into the program’s T&E plan. The T&E IPT should

5 DoD Test & Evaluation Management Guide- Sixth Edition: Dec 2012,


21

be established and chartered as early as possible around MS A so it can be involved

in all the relevant planning and discussions.

Figure 4 - Summary of required document elements for EMS Survivability

Figure 5 - Compliance steps throughout the JCIDS process


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6. Concept for an EMS Survivability Scorecard The scorecard approach works as follows: Requirements generation offices, in consultation with

program offices, for all applicant systems will complete an online survey prior to submitting each

capability requirements document to evaluate compliance with the EMS Survivability KSAs. The level of

compliance will be determined by the number and type of desirable techniques, components and

technologies that it incorporates into its requirements. Upon the completion of the questionnaire the

survey tool will automatically calculate a score for each of the attributes. The scores are weighted or

adjusted according to the type of system. This will ensure that only applicable answers will be factored

into a final score. Those systems that score poorly (an indication of low emphasis on desirable spectrum

attributes) can expect additional scrutiny or possibly even rejection to proceed to the next milestone.

The goal of the EMS Survivability scorecard is to ensure that programs are made aware of and consider

the use of these technologies, not necessarily to guarantee that new systems are as spectrally efficient,

flexible, adaptable, resilient and multi-functional as theoretically possible. There may be numerous, valid

reasons why a program opts for less efficient components or less resilient technologies, but among

them shouldn’t be ignorance of the EMS threats a system will face or a lack of awareness of what design

options are available to achieve greater survivability. These program offices also should be aware of the

true risks involved if they decide to “trade away” spectrum capabilities in favor of other ones.

It is important to understand that no single technology or component is being mandated for

incorporation. The intent is for MATDEVs and PMs to evaluate and carefully consider a variety of

potential technologies and components that can improve the spectrum key system attributes of their

SDS. By incorporating those that make sense from a mission, cost and performance basis, the SDS will be

more survivable, most likely perform better, will be more valuable to the operational user and will help

achieve the goal of EMS superiority in the battlespace.

7. Scorecard Evaluation Criteria Scorecard evaluation criteria are categorized into eight broad categories: Spectrum Protection, RF

Management, Geographical Awareness, Environmental Awareness, Network Efficiency, State

Management and Data Management. Each of these criteria contributes to the five spectrum KSAs in

different and often complementary ways. In combination, they can dramatically improve the

survivability and spectral effectiveness of a system. Additionally, when combined in the battlespace with

other effective systems, they will enable a fantastic level of operational agility. To avoid potential

prescription of capabilities and to promote innovation, these factors do not include a specified level of

performance.

7.1. Spectrum Protection

When developing SP requirements the best approach starts with developing a basic understanding

of a system’s potential spectrum “signature”. This will help determine the relevant frequency bands

and narrow the scope for what exactly needs to be protected. The next step will be to form an

understanding of the EMOE and probable threats a system or platform will likely encounter.

Identifying the regions, countries, terrain (e.g., urban, jungle, mountainous, maritime, etc.),

missions, likely adversaries, domain, (Air, Land, Sea, Space, and Cyber Space) all contribute to this


23

understanding. The final step, particularly for platforms or SoS, is to analyze the entire ‘kill chain” an

adversary might take to defeat/degrade the system using EMS effects. This systematic analysis will

uncover the system’s vulnerabilities and highlight where attention and resources should be directed.

Once these are understood the various aspects of SP listed in this section should be used to inform

the discussions and underpin the debates over what should be required to produce a truly

survivable design vs what might be optional or perhaps unnecessary.

SP includes any EP, ES, DE and EA measures used to protect a system or platform from the effects of

the EMS, whether they are caused naturally, intentionally by an adversary or inadvertently by

friendly or neutral actors. There are many considerations to be taken into account when choosing

the types of SP to employ. The type, power level and sophistication of the SP measures required for

system survivability should be matched to the probable threats. In high threat environments

employing multiple, complimentary technologies as well as appropriate tactics, techniques and

procedures will assuredly be required to ensure survivability. The degree of integration with other

electronic support systems such as threat warning systems will also enhance effectiveness. Finally, a

network of spectrum protection systems can amplify the benefits of using them for point defense. In

all cases a layered defense that doesn’t rely on any single technology or method will provide the

best overall protection against threats. Since the complexity and speed at which EMS operations

often occur is greater than any human can process and react to, the most robust designs must

include a high degree of automation and adaption to achieve the necessary levels of survivability. All

of these considerations must be analyzed in detail before making final design decisions.

This is not an exhaustive list – Attributes like redundancy and skillful employment can contribute

significantly towards preserving a system’s capability. Attributes like speed, maneuverability and

situational awareness provide degrees of benefit for spectrum protection that are difficult to

measure. What is important is to build a practical and effective set of system requirements that will

ensure the necessary degree of survivability.

7.1.1. Resilience

From the standpoint of EMS Survivability this is the most critical aspect of spectrum protection.

Resilience focuses on the ability of the system or collection of systems to support the functions

necessary for mission success in spite of hostile action or under adverse conditions. From a

spectrum specific perspective, resilience is the ability of a system to avoid or withstand the

negative effects of congested and contested spectrum environments without suffering an

abortive impairment of its ability to accomplish its designated mission or function.6 Resilience

has multiple aspects to it. While most aspects are addressed in this criteria a few aspects are

covered under the Adaptability, Spectrum Access Flexibility, Efficiency and Multi-functionality

attributes.

7.1.1.1. Passive Resilience

Over a century of evolving and difficult lessons have been incorporated into the DoD’s

Electromagnetic Environment Effects (E3) instructions, standards and policies. Many

6 See definitions section of the DoD EMS Strategy Roadmap & Action Plan: DoD CIO. Sept 2015


24

instances of mission failure, equipment destruction and loss of life have spurred and

informed this evolution so they must not be ignored. Understanding E3 is a critical first step

in designing and producing resilient systems. Just meeting the common military standards

for SDS equipment design listed below will mitigate most of the passive EMI issues. See MIL-

HDBK-237 (Electromagnetic Environmental Effects and Spectrum Supportability Guidance

for the Acquisition Process) for detailed guidance on how to incorporate E3 and Spectrum

Supportability into JCIDS and other acquisition documents.

DoDD 3222.3 describes the DoD’s E3 program and requires program offices to address E3

requirements during the acquisition process. E3 is defined as the impact of the EME upon

the operational capability of military forces, equipment, systems, and platforms. It

encompasses all electromagnetic disciplines, including electromagnetic compatibility (EMC);

electromagnetic interference (EMI); electromagnetic vulnerability (EMV); electromagnetic

pulse (EMP); electrostatic discharge (ESD); hazards of electromagnetic radiation to

personnel (HERP), ordnance (HERO), and volatile materials such as fuel (HERF); and natural

phenomena effects of lightning and precipitation static (p-static). (JCS Pub 1-02). Meeting

the following prescribed Military Standards will go a long way towards addressing E3 issues.

MIL-STD-469: Interface Standard, Radar Engineering Design Requirements,

Electromagnetic Compatibility

MIL-STD-464C: Interface Standard, Electromagnetic Environmental Effects Requirements

for Systems

MIL-STD-461F: Interface Standard, Requirements for the Control of Electromagnetic

Interference Characteristics of Subsystems and Equipment

DO-160D: Environmental Conditions and Test Procedures for Avionics Equipment

Passive techniques to reduce EMI effects are very common and effective. Passive

components, such as resistors, capacitors, and inductors, are powerful tools for reducing

externally induced interference when used properly. Many of the techniques discussed in

this section are essential to protecting systems from disruption and outright damage that

can be caused by Electromagnetic Pulse (EMP) weapons. The design of the RF sub-system

and digital filtering can greatly affect the performance of the system overall as well. Here is

a list of the most common passive resilience techniques:

7.1.1.1.1. Physical shielding

A properly shielded enclosure is very effective at preventing external interference from

disrupting its contents as well as confining any internally-generated interference. For EA

systems RF barriers are an effective method of shielding friendly and neutral SDS from

the negative effects of jamming. Some examples include:

Encasement – (Metal chassis and cabinets, faraday screens, carbon shields, RF

Gaskets, etc.)

RF Absorption materials (e.g., Carbon impregnated foam, Ferrite tiles, Special paints,

etc.)


25

Connector shielding. Cables provide special problems for shielding because an

unshielded and unbalanced electrical cable can act much like an antenna. Use of

properly rated and shielded cabling as well as connectors and conduit throughout a

systems’ design is critical.

7.1.1.1.2. Noise Reduction

There are numerous ways that undesired noise can couple into a circuit and ruin its accuracy. Examples included Radio broadcasts, lighting, power lines, electric motors) Since little control is possible over these sources of EMI, the next best management tool one can exercise over them is to recognize and understand the possible paths by which they couple into the equipment under design.7 Three very general paths are by:

Interference due to conduction (common-impedance)

Interference due to capacitive or inductive coupling (near-field interference)

Electromagnetic radiation (far-field interference)

Some common techniques to eliminate these issues are:

Employ low impedance electrolytic (LF) and local low inductance (HF) bypasses

Use proper grounding and power planes

Optimize system design with careful wire and component placement

Use twisted pair wires

7.1.1.1.3. Filtering

Both analog and/or digital filters can be used to reduce or eliminate "out-of-band"

noise signals in the system’s digital baseband processor.

The equivalent of filtering can be achieved by incorporating fiber optics into

portions of the design. Fiber optic cables are not susceptible to EM energy and do

not provide an electromagnetic conduit to other components.

Proper incorporation of Transient Voltage Suppressors (TVS) (e.g., Zener diodes,

Metal Oxide Varistors (MOVs)) that are designed to react to sudden or momentary

overvoltage conditions and protect electronic circuits and electrical components.

Robust circuit design for immunity enhancement (ref: IEEE signal integrity).

Use of braid-breakers or noise chokes to reduce common-mode signals.

7.1.1.1.4. Signal amplification

Incorporating robust Low Noise Amplifiers (LNA) to boost weak signals.

7.1.1.1.5. Error Detection and correction

Chip-level error detection and correction algorithms are common and effective

remedies for data corrupted during transmission by in-band noise.

7 Analog Devices, Inc. Tutorial (MT-095) on EMI, RFI and Shielding Concepts, 2009:

http://www.analog.com/media/en/training-seminars/tutorials/MT-095.pdf

http://www.analog.com/media/en/training-seminars/tutorials/MT-095.pdf


26

Forward Error Correction (FEC) or channel coding is a technique used for controlling

errors in data transmission over unreliable or noisy communication channels. The

central idea is the sender encodes the message in a redundant way by using an

error-correcting code (ECC). The redundancy allows the receiver to detect a limited

number of errors that may occur anywhere in the message, and often to correct

these errors without retransmission. FEC gives the receiver the ability to correct

errors without needing a reverse channel to request retransmission of data, but at

the cost of a fixed, higher forward channel bandwidth. FEC is therefore applied in

situations where retransmissions are costly or impossible, such as one-way

communication links and when transmitting to multiple receivers in multicast. FEC

techniques are widely used in modems and network switches8 (also see Section 7.6).

7.1.1.2. Active Resilience

Digital technology has enabled newer and more advanced techniques for filtering noise,

reducing vulnerability and avoiding interference. Several features discussed in previous

sections can significantly improve the resilience of systems to interference. Employed

together with the technologies and techniques discussed here, these can produce a highly

robust and resilient design that can perform well in most congested and contested

environments.

7.1.1.2.1. Adaptive signal processing

More sophisticated than fixed analog or digital filtering; adaptive signal processing

constantly samples the noise floor and optimizes the filter accordingly. Constant

False Alarm Rate (CFAR) receivers on some RADARs are just one example of this

technique.

Adaptive/Transversal equalizers improve the digital system performance in the

presence of multipath fading and/or linear distortion. These adaptive equalizers

reshape the pulse so as to minimize intersymbol interference (self-generated noise).

An approximate 4 to 6 dB improvement in the composite fade margin can be

achieved with such equalizers in a 64 QAM (Quadrature Amplitude Modulation)

receiver. Their major drawback is their expense.

7.1.1.2.2. Interference Cancellation

Digital processing can be used to cancel or subtract out interfering signals that meet

certain criteria. There are multiple variations on this technique that can be used

selectively or in combination to achieve better performance and reduce

vulnerability in congested and contested environments. Adaptive antennas can

amplify the benefits of this technique by allowing the cancellation of signals from

specific (or multiple) directions. In congested and/or contested bands where noise

levels are high, cancellation techniques will be crucial to maintaining system

8 Wikipedia - https://en.wikipedia.org/wiki/Forward_error_correction

https://en.wikipedia.org/wiki/Forward_error_correction


27

effectiveness without resorting to high power levels or the constant retransmission

of data which can dramatically reduce overall efficiency and increase vulnerability.

7.1.1.2.3. Spread-Spectrum & Wideband Technologies

Spread-spectrum techniques generally makes use of a sequential noise-like signal

structure to spread the normally narrowband information signal over a relatively

wide band of frequencies. The receiver then correlates the received signals to

retrieve the original information signal. Spread-spectrum techniques can

significantly reduce a systems vulnerability to jamming as well as lower its

probability of being intercepted.

Frequency-hopping spread spectrum (FHSS), direct-sequence spread spectrum

(DSSS), time-hopping spread spectrum (THSS), chirp spread spectrum (CSS), and

combinations of these techniques are forms of spread spectrum. Each of these

techniques employs pseudorandom number sequences created using

pseudorandom number generators and known by both the transmitter and receiver

to determine and control the spreading pattern of the signal across the allocated

bandwidth. As a general rule, the faster the frequency-hopping rate the better.

Ultra-wideband (UWB) is another modulation technique that accomplishes the same

purpose, based on transmitting short duration pulses. For example the ubiquitous

WiFi standard IEEE 802.11 uses either FHSS or DSSS in its radio interface.

A more advance spread-spectrum technique is Adaptive Frequency-hopping spread

spectrum (AFH) (as used in Bluetooth) which improves resistance to radio frequency

interference by avoiding crowded frequencies in the hopping sequence. This sort of

adaptive transmission is easier to implement with FHSS than with DSSS. AFH must

be complemented by a mechanism for detecting good/bad channels and then

dynamically “notching” them out from being used.

Simultaneous multi-band operation (Carrier aggregation) – Spreading out a signal

does not require the use of contiguous spectrum. Portions of multiple bands can be

used to either improve access, improve mission effectiveness or in the case of

resilience, to avoid interference. Creating a wide, virtual channel by synthetically

stitching together multiple non-contiguous sections of spectrum can allow SDS to

operate in more locations or use more optimal modes that would otherwise not be

possible. Several RADARs have successfully leveraged multi-band techniques to

optimize effectiveness and deceive detection.

7.1.1.2.4. Null steering/spatial nulling (Mechanical or electronic)

Nulling involves blocking or “not-listening to” signals (A technique that turns off

reception of signals which arrive at a particular elevation and azimuth). These can

range from simple metal shields that block signals from a particular sector to

advanced digital arrays that can precisely steer a null to any point in the field of

view. This can produce significant improvements in Signal + Interference to Noise


28

Ratios (SINR) and thus greatly enhance performance. It is also an effective anti-

jamming technique.

7.1.1.3. Cooperative Resilience

As the name suggests such strategies take advantage of the diverse nodes of systems to

provide mutual “cooperative” benefit. In most cases such cooperation requires some level

of data fusion and intense processing capacity.

7.1.1.3.1. Interference alignment (IA)

IA is a linear precoding technique that attempts to align interfering signals in time,

frequency, or space. In MIMO (Multiple In Multiple Out) networks, interference

alignment uses the spatial dimension offered by multiple antennas for alignment. The

key idea is that users coordinate their transmissions, using linear precoding, so that their

mutual interference aligns at the receivers, facilitating other simple interference

cancellation techniques.

7.1.1.3.2. Cooperative Communications

Cooperative Communications generates greater spatial diversity in networks. Multiple

nodes relay each other’s signals thereby improving the chances of a signal making it to

the destination receiver and often circumventing areas of strong interference. One can

think of a cooperative system as a virtual antenna array, where each antenna acts as a

partner that listens to transmissions within the network and retransmits them in a

collaborative fashion. Such cooperation renders jamming by an adversary less effective.

7.1.1.3.3. Multi-Static Radar

This is the use of netted radars or multiple transmitters and receivers to create a

spatially diverse area of shared radar coverage. While such systems often exhibit

significantly better target detection, resolution and classification than traditional radars,

they also can improve basic resilience. The spatial diversity allows the system to take

advantage of the most favorable propagation paths, to avoid the effects of jamming and

EMI and to add redundancy.

7.1.2. Graceful Degradation

Another key design concept for effective SP is “Graceful Degradation.” No amount of spectrum

protection will ensure that a system will be able to perform its mission in all scenarios. To

ensure the highest reliability and operational readiness, a building block approach to system

design should be utilized. The basic blocks are interconnected so that an individual malfunction,

(due to equipment failure, battle damage or EMI perhaps) will not disastrously degrade or

inhibit the operation of the total system. Graceful degradation is achieved with a multiple-

function design approach that enhances total system survivability by prioritizing and preserving

a minimum number of functions to be performed that permit mission completion.

Graceful degradation is utilized in a system design that employs a network of similar items. The

entire design must be analyzed to identify any single points of failure. For these, parallel

network paths and redundant nodes must be provided to ensure that an additional load can be


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carried when elements fail. This can reduce degradation to a tolerable level. In other words, an

element failure in a parallel path or redundant node will not automatically cause complete

equipment failure, but instead merely degrade equipment performance.

In IT systems, the clever design of software can provide a significant level of graceful

degradation. One example would be to use automated controls that can dynamically group and

prioritize functions, and then adjust or turn-off those functions not essential for the current

mission. Much more than good software or complex switching is required however. The

successful application of the graceful degradation concept requires that supporting system

designs (e.g., cooling, power, performance monitoring, etc.) also support the graceful

degradation. Paying close attention to these other design considerations can help ensure that

critical mission functions can continue despite partial failures or disruptions.

Graceful degradation requires the application of such design considerations as load sharing,

functional modularization, alternate pathways, reconfiguration, minimum safe-state operation,

anomaly detection & isolation, operator alerting and selective redundancy. When done well

these design considerations achieve basic system performance reliability with a minimal

increase in complexity, providing a pay-off in high system survivability.

7.1.3. Wartime Reserve Modes (WARMs)

As the name suggests WARMs are operating modes or capabilities (or procedures) that are held

in reserve for wartime or emergency use. These serve to hide the characteristics and full

operating capabilities of any variety of systems. Since the effectiveness of our systems partially

depends upon their full capabilities being undiscovered or at least misunderstood by an

adversary, relegating their use to wartime is highly effective for preserving the advantages they

provide. They can take many forms but usually involve the employment of previously used (or

combinations of) operating parameters in new ways (perhaps varying the signal bandwidth or

employing an entirely unknown capability or level of performance. The reprogram-ability of

today’s software driven systems allow for WARMs to be stored securely in the lab and brought

out to be loaded just prior to a conflict. The better WARMs are at least as effective as the

peacetime modes and even more difficult to characterize and counter. The best ones are

engineered and tailored for specific adversaries and scenarios.

A corollary to the wartime reserve mode is to intentionally limit or govern certain operating

parameters or even whole capabilities during peacetime or even during low-intensity conflicts. If

our systems do not broadcast the full measure of their capabilities our potential adversaries are

less likely to exploit and counter them effectively before conflict breaks out. By installing

performance “governors” on a system one can effectively protect our investment and preserve

the element of surprise for use in medium or high-intensity conflict.

While not as effective as a WARM but still useful, a system can be programed to only use its full

capabilities when Low Probability of Detection/Low probability of Interception (LPD/LPI)

measures are installed and operating. This reduces the chances that a system’s full capabilities


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can be detected, exploited and countered. Such restrictions must be carefully applied so as not

to unnecessarily hamstring operational capabilities.

System developers should strive to develop multiple WARMs. The employment of many of the

adaptable, flexible, efficient and multi-functional system design features in this guidebook will

only multiply the number of potential WARMs that system designers can imagine and develop.

7.1.4. Countermeasures

System resilience is rarely enough to provide the level of protection needed for effective

operation in contested EMOEs. Adding layers of defense through countermeasures is an

effective strategy. An electronic countermeasure is an electrical or electronic device designed to

mask, trick or deceive RADAR, SONAR or other detection systems, like infrared (IR), electro-

optical (EO) or lasers. It may be used both offensively and defensively to deny detection and

targeting information to an enemy. The system may make many separate targets appear to the

enemy, or make the real target appear to disappear or move about randomly. Other

countermeasures are disruptive enough to essentially render an adversary blind, deaf and/or

mute so to speak. While most commonly used to protect platforms from guided missiles they

can be used to protect a variety of platforms and fixed targets from various threats.

7.1.4.1. Passive Countermeasures

Simply put, a passive countermeasure is one that does not require the emission of

electromagnetic energy. By their very nature these are relatively easy to employ and often

difficult for an adversary to overcome.

7.1.4.1.1. Emissions control

This is an underappreciated method of reducing vulnerability to EMS threats. Whether

emanating from spurious, out-of-band emissions from poorly designed SDS, leakage

from a system with inadequate shielding (See MIL-STD-461B/C) or a transponder that is

inadvertently left on by the operator, unintended emissions of electromagnetic energy

can provide an adversary with numerous opportunities to detect, track, identify and

attack a system. Unintended emissions are also a major cause of frequency fratricide.

Against sophisticated adversaries the potential can be assumed that nearly any radiation

above the noise floor is susceptible to detection so attention to these details is crucial

for operating in high threat environments. Therefore, a SDS that indicates the status of

its operation is essential. For platforms or SoS, the analysis should begin with gaining an

understanding of the platforms’ entire spectrum “signature” or all the potential

emissions that the various SDS onboard might make. Designs that include the remote

monitoring of the status of all hosted SDS and that impose proactive or automated

controls on all sources of radiation will improve survivability. Even better are ones that

employ independent RF monitoring to alert the operator to any leaks and squeaks.

7.1.4.1.2. Stealth

Stealth technologies (also termed Low Observable (LO) Technologies) cover a range of

techniques used to make systems (usually platforms) less detectable across the EMS.


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While techniques for reducing the infrared, visible and ultra-violet signatures of systems

are certainly applicable, these are discussed in section 7.1.5, Light Wave Threat

Protection, below. This section focuses primarily on techniques to reduce a system’s

Radar Cross Section (RCS) which is the primary determinant of detectability by RF

sensors, particularly RADAR.

There are several techniques for reducing a system’s RCS. As with many other

techniques discussed in this guidebook, it is most effective to use combinations of them

in a highly integrated and complimentary manner. Employing systems with effective

TTP that leverage their stealth properties is also crucial and should not be neglected.

• A platform’s shape has a significant impact on RCS. While no shape is 100%

“transparent” to RADARs, as a general rule, a smooth surface with fewer bumps and

protrusions will be less detectable. Masking intakes and moving parts like wheels or

propellers will reduce RCS by a surprising amount. Another technique used in

stealth designs is to align leading edges parallel to each other. This technique

reduces the number of edge orientations in the shape of the structure.

• The type of material and structure will affect RCS. While most metals like aluminum

are highly reflective, certain materials and composites do not conduct or reflect

electromagnetic energy and therefore can be very beneficial in reducing RCS. Since

RCS is highly dependent upon the aspect of the target to the detector, selective use

of such materials and structures on the most sensitive or exposed parts of a

platform is one useful technique.

• Radar-Absorbent Materials (RAM) function to absorb radiated energy and converts

it to heat rather than reflect it back.9

7.1.4.1.3. Threat Detection & Warning

While technically this is an electronic support measure and not a passive

countermeasure, effective employment of nearly all electronic countermeasures

depends upon timely threat detection and warning information. The best such systems

provide very fast queuing, accurate angle-of arrival information, and advanced

processing to detect and declare threats even in cluttered environments. Whether

incorporated organically into a system or coupled with a separate dedicated warning

system, threat detection & warning are critical components of system survivability in a

contested EMOE.

7.1.4.1.4. RF Decoys

Decoys often offer the most cost effective and lowest risk methods of CM. RF Decoys act

as preferential targets by luring enemy sensors away with much larger cross sections

than the host platform. They come in many varieties and can be expended, towed, self-

propelled or planted in fixed sites. Simple decoys like chaff dispensers rely on clouds of

9 See Wikipedia article on Stealth technology: https://en.wikipedia.org/wiki/Stealth_technology


32

highly reflective material, usually sized to multiple wavelengths, to lure a radar seeker

away from the target. More sophisticated, software controlled decoys, modulate the

targeting radar’s return (echo) signal to indicate a false range as well as to increase echo

strength to give the appearance of a larger target. Even more sophisticated ones can

operate persistently and autonomously to mimic multiple RF signatures of a target.

7.1.4.1.5. Anti-jamming/Anti-spoofing

There are a variety of techniques that can be employed (in concert or separately) to

reduce or negate the adverse effects of operating in a contested EMOE. To employ any

of them requires awareness that the system is the target of jamming or spoofing which

is not always obvious. Otherwise jamming/spoofing must be assumed and the

countermeasure continuously employed which is not normally optimal for performance.

For systems without dedicated threat detection and warning sensors, sophisticated

software algorithms can piece together enough clues to adequately recognize jamming

or spoofing thus triggering an appropriate countermeasure. When detected and

recognized, jamming and spoofing can sometimes be filtered out or ignored. Other

techniques employ adaptive measures like altering operating parameters (Power,

Frequency, Waveform, Data throughput, etc.) in order to maintain a sufficient level of

effectiveness or quality of service. Many of these techniques are discussed in the

sections below on RF Management and Network Management.

7.1.4.2. Active Countermeasures

Relying upon system resilience and passive measures may not provide the level of

survivability required for many systems in high threat environments; particularly expensive

platforms. Complimenting these with some active techniques described below should also

be considered to increase survivability and help deny or defeat an adversary’s attempts to

use the EMS against a friendly target.

7.1.4.2.1. Defensive Electronic Attack (DEA)

Sometimes referred to as self-protection jamming or Electronic Countermeasures, such

measures are designed to disrupt or foil an adversary’s ability to detect, track, target or

attack using the EMS. Whether this is to defeat an incoming radar guided missile or to

jam the trigger mechanism of an IED, DEA equipment is used by many types of systems

and platforms in the modern battlespace. Broadly speaking there are two forms of self-

protection jamming: noise jamming and deception jamming. Noise jamming

(Incoherent) uses relatively high intensity transmitted power to overwhelm a target

receiver with incoherent “noise.” Deceptive jamming (Coherent) uses false signals that

an adversary’s equipment accepts as real.

The effectiveness of jamming is not a direct linear function of increasing power. Factors

like geometry, the technique used, and the particular target being jammed are also

critical. In fact, for certain sophisticated targets with the proper signal processing and


33

electronic counter-counter measures (ECCM), merely increasing power could trigger

special anti-jamming modes and actually reduce effectiveness.

While some legacy systems are still manually operated, most newer ones are highly

automated. The more versatile jammers can jam multiple signals operating in wide

frequency ranges and can adapt to evolving threats. Most DEA systems are integrated

with threat detection & warning receivers as well as decision processors which decide

when and how countermeasures should be employed. Evolving schemes involve the

coordination of multiple DEA systems to achieve a more distributed effect. One last

consideration is that few systems today record operational data. This can be critical to

support rapid mission adaptation and reprogramming of ES/EA/EP systems.

7.1.4.2.2. Spoofing

This is a form of deception jamming in which signals representing false or counterfeit

information are deliberately transmitted to an adversary to cause confusion (e.g.,

RADAR spoofing to present false targets). A variety of techniques of varying

sophistication have been developed over the last century to provide a range of

protection levels. Specialized spoofing techniques have even been devised to cause

premature detonation of certain types of munitions like artillery rounds with proximity

fuses. Another spoofing technique that has become more common for radar spoofing is

the use of Digital Radio Frequency Memory (DRFM) which digitally captures and

retransmits a radar signal. Being a coherent representation of the original signal, the

transmitting radar will not be able to distinguish it from other legitimate signals it

receives and processes as targets. In many cases special software can be develop to

detect and counter anomalies associated with spoofing attempts (e.g. Selective

Availability and Anti-Spoofing Module {SAASM} for GPS receivers).

1.3.2.2.1. Masking

This is the controlled radiation of electromagnetic energy on friendly frequencies in a

manner to protect or “mask” the emissions of friendly communications and electronic

systems against an adversary’s electronic warfare support measures and signals

intelligence without significantly degrading the operation of friendly systems. Certain

types of ECM techniques are designed to blanket a targeted area/sector with broadband

noise thus allowing friendly systems to operate behind this virtual “screen” with little

fear of being detected or targeted.

1.3.2.2.2. Meaconing

This is a form of deception where navigation signals are intercepted, manipulated and

rebroadcast on the received frequency, typically with power higher than the original

signal, to confuse or deceive an adversary’s navigational systems. Consequently,

navigation receivers are given inaccurate bearings, positioning and/or timing

information. While predominantly used for offensive reasons, meaconing could

potentially be used to thwart a threat and be considered a form of spectrum protection.


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7.1.5. Light Wave Threat Protection

From an SP perspective, survivability considerations for light wave threats (Infra-Red, Visible,

Ultra-Violet) are quite similar. While IR threats are the most common, there are many in the

visible and UV ranges as well. No matter which the subtle differences, they are all measures

designed to conceal or deceive the sensors used by an adversary to detect, track, characterize or

target a system. Multiple considerations must be factored in to determine the effectiveness of

these measures (e.g., target speed, aspect, and maneuvering capability, countermeasure timing,

dispersal patterns, duration, etc.) however, the basic protections measures are similar. These

methods are often most effective when paired with threat detection systems and when

employed in combinations or in automated fashion. Proper Tactics Techniques & Procedures

(TTP) will also boost their effectiveness.

7.1.5.1. Vulnerability Reduction

Clever design features can significantly reduce the vulnerability of platforms to light wave

threats. Examples include employing additional shielding to reduce signatures, refractive

coatings, relocating critical components away from hot-spots, cooling or diffusing exhaust

plumes, locally hardening fixed critical components, moving hot-spots to less vulnerable

locations, using sacrificial structure, and improved fire suppression systems & techniques.

7.1.5.2. Camouflage

Perhaps the oldest form of deception, camouflage involves disguising personnel, equipment,

installations, etc. to prevent or delay detection. While primarily a consideration for visible

light sensors, examples do exist for IR and UV wavelengths. In as much as camouflage can

effectively reduce detection from IR, EO an UV sensors they can be considered forms of

spectrum protection.

7.1.5.3. Masking/Screening

Like camouflage, masking/screening is a technique to obscure or hide a target but in this

case employing expendable and temporary clouds of light-diffracting material. The

performance of light dependent sensors can be significantly degraded by phenomena like

fog, rain, snow, smoke, etc. While simple smoke generators can work for fixed or slow

moving surface targets, pyrotechnics or rapid blooming aerosols are required for fast

moving ones like speedboats and aircraft. This countermeasure is often employed in

conjunction with other techniques such as flares and evasive maneuvering in last ditch

efforts to evade missile threats. It can also be deployed in pre-emptive attack profiles to sow

confusion or delay detection.

7.1.5.4. Decoys

Broadly speaking, decoys are any devices used to deceive an adversary or a sensor by

mimicking the light wave signatures of a real target. A wide variety of different types have

been developed over the years to mimic the light signatures (IR, Visible and UV) of facilities,

ground vehicles, aircraft, ships and even personnel. They also vary in sophistication and

persistence from simple expendable flares to self-propelled multi-wavelength decoys that

can be networked into a comprehensive system of protection measures.


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7.1.5.4.1. Flares

These are a particularly common form of decoy. Flares are expendable IR

countermeasures that produce intense heat to mimic that of an engine or other system

hot spot. They function to attract a heat seeking sensor away from the target and have

evolved over the decades to keep pace with evolving threats. The better ones can

produce the same wavelength of heat as the targets they are designed to protect and

last long enough to allow the target to successfully evade. While they can be manually

activated they are usually more effective when automatically deployed for optimal

dispersal and timing. More effective flares can propel themselves over a flight path

similar to, but divergent from, the path of the target platform. This is to confuse missile

seekers that can discriminate between a flare traveling ballistically and a propulsion-

powered object such as a ship or aircraft. Even more integrated and sophisticated

protection systems will employ “cocktails” of different flares and countermeasures in

tailored combinations and patterns to improve the level of protection.

7.1.5.5. Dazzlers

These are countermeasures to foil Electro Optical (EO) and IR sensors. They produce

bright flashes to disorient or disrupt the sensor; essentially blinding it. Early models used

pyrotechnics to produce the desired effect but almost all current versions are laser

based. The most prolific varieties are designed to counter heat seeking missiles. One

such system is an Infra-Red Countermeasures (IRCM) Pod. This produces a modulated

source of infrared radiation with a higher intensity than the target. When “seen” by a

missile seeker, it overwhelms the signal from the engine and provides incorrect steering

cues to the missile. The missile will begin to deviate (wobble) from the target, rapidly

breaking lock. Once an infrared seeker breaks lock (they typically have a field of view of

only 1 - 2 degrees), they rarely reacquire the target.

EO/IR seekers have evolved to be less susceptible to deceptive countermeasures.

Modern imaging IR seekers (IIR) can ignore countermeasures that are not in the same

frequency range or at a similar intensity level as the initial target. They can also

discriminate based on target size and shape. Tracking logic has improved to where

seekers can ignore targets that diverge from the initial target at unrealistic rates such as

those presented by many expended flares. Multi-Wavelength sensors can

simultaneously detect and track targets in wavelengths such as IR, visible and UV

making them highly effective and extremely difficult to counter.

To keep pace, more sophisticated countermeasures have been developed to improve

the deception. Directional IRCM (DIRCM) pods allows for a countermeasures laser to be

targeted directly at an incoming IR threat. This makes possible a more powerful and

effective defense than previous, non-directional infrared countermeasures, as the

threat is directly addressed rather than the system essentially painting an area with IR

disruption which results in a weaker signal in any given direction. Multi-wavelength

DIRCM pods have the advantage of tailoring their laser pulses to match that of the


36

missile seeker or even peppering it with pulses at multiple frequencies, thus providing

even greater effectiveness.

7.1.6. Laser Protection

While technically lasers are light wave threats, their characteristics and the unique methods of

protection against them warrant a separate discussion. Such protection measures are best when

combined with laser warning systems which detect if the platform has been illuminated by a

range-finding or targeting laser.

7.1.6.1. Filters

Laser filters are used to reject an undesired wavelength or range of wavelengths while

transmitting wanted wavelengths for a number of laser applications. Laser filters are

designed using a variety of substrates, coatings, or a combination of the two to reflect the

undesirable wavelengths, while allowing all other light to be transmitted. Lasers capable of

damaging components at extended ranges only utilize a few, well know wavelengths.

Consequently, filters tailored to these wavelengths provide adequate protection in most

cases for sensors and other sensitive components. Laser filters include optical filters such as

bandpass, longpass, or notch. Many dichroic filters are also available for narrow wavelength

selection or transmission widths. The advantage of such filters is that the underlying sensor

continues to function normally even while being attacked by a laser weapon.

7.1.6.2. Shutters

Laser shutters work in conjunction with an optical sensor to protect a vulnerable

component. When the optical sensor detects high energy light waves in designated

wavelengths, it instantaneously signals the shutter to close thus shielding the underlying

system or component. The advantage of shutters is that they can protect against multiple

wavelengths of laser weapons as well as against some more powerful lasers that can

damage the protected component. The disadvantage is that the sensor will be effectively

“blinded” for the duration of time the shutter is closed.

7.1.6.3. Anti-laser Aerosols

The performance of lasers can be significantly degraded by phenomena like fog, rain, snow,

smoke, etc. Leveraging the same idea of light diffraction, aerosols work by rapidly dispersing

ultrafine, reflective particles into the area around the target. The laser beam hitting these

particles would disperse (an effect called “blooming”) just as if it hit a dust cloud even

though to the naked eye the area would appear only mildly hazy. Depending upon the

weather and wind conditions the effect can last many minutes. The reflective particles are

most effective when designed for the particular wavelength of the laser.

7.1.6.4. Shielding

Protections against high intensity laser weapons designed to burn, deform or penetrate

structures are similar to protections against kinetic weapons. They are essentially forms of

armor. For conventional forms, heavier and denser materials generally perform better.

Specialized laser armor may also be utilized. Highly reflective coatings, particularly in the


37

exact color of the laser, can effectively reflect laser energy but are often impractical in

battlefield applications. Ablative armor is usually made of an array of tightly-clustered gel or

foam packs. When a laser hits one of these packs, the heat from the laser instantly boils the

gel or foam away, the explosive reaction almost instantly absorbing, dispersing, and

redirecting most of the laser energy away from the target. This is much like modern day

explosive reactive armor, but carried out on a much smaller scale. However unlike reflective

surfaces, ablative armor would not be effective if hit more than once in the same spot.

Another specialized armor uses superconducting wire woven into the armor to absorb the

incoming electromagnetic energy and instantly disperse it outwards away from the impact

point thus diffusing the energy. No matter which type is chosen, they all present similar

design trade-offs as conventional armor (e.g., space, weight, cost, etc.).

7.2. Radio Frequency (RF) Management

A number of advanced functional attributes will be critical to incorporate into the types of SDS desired for the future. Ones that apply specifically to a system’s RF component include: frequency agility, bandwidth management, modulation management, power management, and antenna management. Each contributes to the system’s ability to exhibit one or more of the desired EMS Key System Attributes. For example, a modern AESA RADAR is considered to be extremely agile from a RF Management perspective. Among its many advantages it can change frequencies with every pulse (usually using a pseudo-random sequence); form multiple beams or sequences and patterns of beams, spread the frequencies across a wide band even in a single pulse, change power output in every pulse, and rapidly change the modulation of the signal. Such extremely variable signal output will normally be interpreted as random noise by an adversary’s radar detectors. In addition to vastly increasing the effectiveness of the RADAR, these capabilities support all six of the EMS KSAs thus highlighting the key role of RF Management as a critical criteria in system survivability.10

7.2.1. Frequency Agility

Frequency agility allows a system to utilize a variety of frequencies. Greater flexibility in

frequency tuning range provides multiple benefits. This will allow a system to be accommodated

in available allocated bands and in more locations. Depending upon how it is implemented it will

reduce detectability and improve survivability. Using unused frequencies from a frequency

resource list improves the overall spectrum efficiency of a system. As an added bonus this

attribute improves the global supportability of a system.

7.2.1.1. Frequency Tuning Range

It is desirable for SDS to have the capability to operate over as wide a range of frequencies

as possible. This attribute will allow them to take advantage of less subscribed bands when

necessary. In effect, this allows more devices to be squeezed into the same amount of

spectrum. Since allocated service for any given frequency range varies from ITU region to

region and from country to country, flexibility in tuning range increases the chances that its

use will be accommodated in many locations. Wide tuning ranges enable SDS to mitigate or

even avoid detection and electronic attack and supports multi-functionality.

10 “Electronic Warfare and Radar Systems Engineering Handbook”, Pgs 116-118: NAWCWD TP 8347, Fourth Edition, Naval Air Systems Command, 2013


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7.2.1.2. Frequency Sharing

Dedicating frequency assignments to stations exhibiting less than full-time use is inefficient.

Sharing a frequency or pool of frequencies is much better. Spectrum dependent devices that

share common frequency resource pools can vastly increase the “occupancy” of a frequency

band. This can be accomplished through several techniques such as a central network

management system, by frequent reference to a centralized database or by sensing the

environment and instantaneously selecting the optimal frequency for use from the common

frequency resource pool. In the extreme, dynamic spectrum access radios can select open

frequencies opportunistically without a pre-designated resource pool. Frequency sharing is

the very essence of flexibility and also promotes survivability and multi-functionality.

7.2.2. Bandwidth Management

This is a key attribute for system adaptability that supports all other attributes of EMS

Survivability. For instance occupied bandwidth is one of the common measures of spectrum

efficiency and is directly related to the amount of information being communicated. Active,

internal management of it can yield significant gains in efficiency and flexibility and is an

important factor in certain survivability techniques.

7.2.2.1. Variable Bandwidth Management

Fixed bandwidth systems with variable data rates are inefficient in their use of the

spectrum. Such systems are also inherently more vulnerable to detection than ones with

variable bandwidths. Therefore it is desirable for SDS to be capable of automatically

adapting their bandwidth in response to mission requirements. A SDS should occupy an RF

bandwidth commensurate with its information exchange requirement (or a sensing

requirement in the case of a RADAR). Optimally, this should be accomplished as rapidly as

the data rate or mission requirement changes. Rapidly varying the bandwidth also reduces

susceptibility to detection and characterization by an adversary.

7.2.1.2. Unintentional Emissions Control

Spectrum‐dependent devices must conform to regulatory limits on unintentional emissions

such as spurious and harmonic emissions. In a co‐sited environment such emissions may

cause interference, mission degradation and inefficiency. National administration and

Military Standards such as MIL‐STD 461, specify these limits. Therefore systems must be

evaluated for compliance (See NTIA Red Book, Chapter 5, for more details).

7.2.3. Modulation Management

Modulation management is a desirable feature for adaptable SDS and is a key factor in multi-

functionality. Variable modulation is also inherently less vulnerable to detection (e.g., Variable

pulse width and repetition frequency in some RADARs). This attribute supports the traditional

consideration of modulation efficiency and the historical trend to support narrow bandwidths at

lower operating frequencies and wider bandwidths at higher operating frequencies thus

enabling a high degree of system flexibility.


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7.2.3.1. Adaptive Modulation

Modulation is important in the determination of spectrum requirements, efficiency,

spectrum protection and multi-functionality. Numerous modulation strategies exist for SDS

with varying efficiencies and effectiveness. Certain modulations schemes are more

inherently efficient and should be studied for adoption whenever practical. Some SDS

employ adaptive modulation which optimizes performance by changing the modulation,

coding, and other signal and protocol parameters to the existing or forecast conditions on

the channel. Others employ adaptive transmission timing to reduce EMI or to reduce the

probability of detection (e.g., Burst mode). Ideally the process of adaptation is a dynamic

one where the parameters change as the radio link conditions change. At the high end of

the scale, adaptable SDS can employ multiple modulation strategies to fit the mission,

function and environment. Adaptive modulation systems usually exhibit better performance

and resilience compared to those that are more static.

7.3.1.1.1. Adaptation Speed

Modern computer processors have become so fast that they are enabling a revolution in

SDS capability. From an EMS survivability viewpoint this translates into increased speed

and agility. As a general rule of thumb, the faster that one’s system can manipulate its

own operating parameters and adapt its modulation the better. Systems exist that can

change their operating parameters many thousands of times per second making the

detection of their emissions (and employing CM against them) extremely difficult.

7.3.1.1.2. Non‐Contiguous Bandwidth Use (Carrier Aggregation)

Traditionally, lower operating frequencies have been allocated for narrower bandwidths

and higher operating frequencies have been allocated for wider bandwidths. Lower

operating frequencies (< 3 GHz) however, exhibit better propagation characteristics

than higher operating frequencies for many applications and are therefore prized for

many types of tactical systems. Accommodation of wide bandwidths (> 1MHz) below 3

GHz is difficult because of historical management practices, regulatory constraints, and

existing frequency assignments. Yet, wider bandwidths can accommodate far greater

throughput to support the data rich applications of the modern military. Therefore, it is

highly desirable for future SDS to be flexible and adaptable enough to utilize large

virtual bandwidths, composed of multiple narrow bands, which can be accommodated

at lower operating frequencies.

7.3.1.1.3. Regulatory Parameter Adaptability

Military SDS must be able to operate in multiple geographic areas; many worldwide.

One previous study11 identified over 140 attributes that are regulated by spectrum

management worldwide. Not all attributes are regulated for all allocated frequency

bands but designing SDS to meet all of these variations and combinations is expensive

and often impossible. A far better approach would be to design SDS than are

11 J. Michael O’Hehir and Alice Kraus, Spectrum Regulatory Information Model, JSC‐CR‐04‐80, Annapolis, MD:

DoD JSC, (Jan 05 draft to be published).


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reconfigurable (either automatically or manually) enough to adapt to multiple

regulatory environments. Such adaptation is also essential to take advantage of

opportunities (ones that improve efficiency, reliability, flexibility, etc.) that are

situationally or time dependent. Regulatory parameter adaptability can allow systems to

manage performance and reduce vulnerability to EMI. It is therefore highly desirable for

SDS to be capable of adapting their frequency, modulation and waveform characteristics

to suit not only the regulatory requirements but the operational needs as well.

7.2.4. Power Management

This is another key attribute for system adaptability that underpins multiple other factors of

EMS Survivability. With the exception of passive listening systems, all SDS can achieve lower

vulnerability, greater spectral efficiency and reduce interference to other devices by managing

their power output to the minimum levels necessary to maintain mission effectiveness. In the

mobile tactical environment, radio link distances vary on a second-to-second basis. Using the

minimum power required to maintain an operational acceptable link will reduce the effective

spectrum footprint and promote frequency reuse within the operational environment. This and

other considerations, such as jam resistance, probability of detection and battery life demand

that spectrum‐dependent systems be capable of dynamically adapting their power output; the

more automated and precisely this can be accomplished the better.

7.2.5. Antenna Management

Advances in antenna technologies offer many operational benefits such as cancellation of

interference, elimination of multi‐path effects, increase in frequency reuse, and reduction in the

probability of detection. Future integration of adaptive array antennas will produce increased

frequency reuse and network throughput. This is yet another highly desirable attribute for

systems developers to incorporate into future SDS that will yield high payoffs and multiple

benefits.

7.2.5.1. Adaptive Antennas Systems (Directional Antennas)

Adaptive antennas can focus their transmit energy to a desired direction (For example,

directly towards a receiver). Conversely, they can focus signal reception to a desired

direction. The technique is sometimes referred to as beamforming (alternatively as

beamsteering or beamshaping). It works by adjusting the width and the angle of the

antenna radiation pattern (a.k.a. the beam). Such antennas can typically also employ signal

nulling to increase resilience or improve performance. A recent study12 has demonstrated

that the use of directional antennas at both ends of the link can significantly increase the

amount of frequency reuse within a tactical environment. Another study13 identified the full

range of benefits associated with the adoption of adaptive array antennas that include

increased transmission rate, increased capacity, increased range, improved signal

12 R. Albus, et al., Operational Implications Assessment Of Smart Antennas, JSC‐CR‐03‐065, Annapolis, MD:

DoD JSC, July 2003. 13 Homer Riggins, et al., Advanced Technology Assessment of Smart Antennas, JSC‐CR‐03‐028, Annapolis,

MD: DoD JSC, July 2003.


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processing, reduced multi‐path interference fading, simultaneous mission employment, far

lower probability of interception/detection and increased security. Due to the tremendous

advantages these antennas produce, they should be actively considered in new or even

existing SDS upgrades when appropriate.

7.2.5.2. Multi‐Path Effects Awareness

Adaptive array antennas can be used to detect and mitigate the negative effect of a multi-

path environment. They can also exploit multi‐path techniques that increase data

throughput by utilizing multiple same-frequency channels. This provides a degree of system

flexibility and adaptability that most legacy systems do not exhibit.

7.2.5.3. Multi-functional Antennas

Choice of antenna design is a critical factor in SDS performance, utility and survivability.

Some systems utilize multiple antennas and can employ them very flexibly to achieve the

desired effects such as improved throughput, better reception, multi-band operations and

redundant path transmission. Examples include electronically steered arrays on many radars

or even modern cell phones which incorporate separate antennas for functions such as

WiFi, Blue Tooth, GPS and LTE. Other systems employ fractal antennas which maintain

excellent performance over a wide frequency ranges or many frequencies simultaneously.

7.3. Geographical Awareness Geographical awareness is a critical enabler for several other technologies and techniques that will support achieving the goals of EMS Survivability. Positioning information will be important in system functions like determining the prevailing regulatory environment, applying a threat posture within a Joint Operating Area, determining relative position to other SDS and for optimizing network performance through the exchange of location information. Orientation and azimuth information is essential for tracking targets, employing directional antennas, or other directional techniques such as null steering. For these and many other reasons, geographical awareness is an important consideration for new SDS.

7.3.1. Location Awareness

Awareness of location can be obtained via several techniques like GPS, beaconing, radio ranging, slaving to external guidance systems or even network determined location. Such knowledge is essential in determining the prevailing regulatory and operating environment. Devices that are aware of their location can be very efficiently utilize limited spectrum allocations and very judiciously modify conspicuous activities in high threat environments. Location information can provide critical awareness of geographical or regulatory constraints on propagation. Such knowledge can also help determine the optimal signal characteristics for the local EME. Lastly, such capability will be essential for employing future strategies such as spectrum sharing, dynamic spectrum access and cooperative geolocation of signals of interest.

7.3.2. Orientation Awareness

Awareness of which direction the host platform is moving and which direction an antenna is pointed is critical for certain functions like geolocation and improving signal gain. While this is an intrinsic capability in most electronically steered arrays it can be useful for a variety of other antenna types. Orientation awareness (both elevation and azimuth) is essential for many types of beamforming techniques and can factor into all five of the desired spectrum attributes.


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7.3.3. Location Information Exchange

Just as geographic self-awareness enables many benefits for the SDS itself, the ability to share that information with other systems and networks can extend and amplify those benefits substantially. Shared position and orientation information amongst cooperating nodes supports the use of directional antennas and reduced network routing overhead. Future spectrum battle management systems are envisioned which will process such information to more accurately allocate spectrum resources and reduce levels of interference or geolocating signals of interest. Use of directional antennas requires knowing in what direction to form the beams or nulls. With the implementation of Mobile Ad Hoc Networks (MANETs) the exchange of location information will reduce formation and reconfiguration times. Knowledge of cooperating nodes locations will also improve network routing strategies. Because of all these benefits, location, orientation and the exchange of such information should be considered in new SDS whenever possible.

7.4. Electromagnetic Environmental Awareness Current centralized frequency assignment practices reserve spectrum for a specific user, application, and location. Implied within the assignment of spectrum is protection from interference from other users for the duration of the assignment. This provides the assigned user with access to the spectrum whether it is used continuously or seldom. Studies have shown that certain overly congested bands are actually less than ten percent occupied at any given moment. To exploit this situation, future spectrum‐dependent capabilities must sense the unoccupied spectrum and access that spectrum within the bounds of the prevailing regulatory and operational constraints. EME awareness is a crucial component of such schemes and also enables significant survivability capabilities that allow an SDS to detect and immediately mitigate threats.

7.4.1. Environmental Sensing

Sensing the local electromagnetic environment is central to the transformation from reservation

management to decentralized and autonomous operations. It will be a key enabler of agile

spectrum operations and for survivability in contested EMOE. Mission performance is

substantially improved by systems capable of employing environmental sensing in conjunction

with RF management (See section 7.2 above). There are several types of sensors of various

levels of capability and sophistication to choose from and to integrate together for synergistic

effect. Examples include:

Energy detection sensors that can detect power levels like a spectrum analyzer or like the

power density matrix.

Cyclostationary sensors that used to pick up statistical properties of signals in time.

Waveform detectors that can look for specific waveforms such as a radar pulse or an OFDM

signal.

Direction Finding sensors that can be used to determine lines of bearing to detected signals

7.4.1.1. Limited Frequency Sensing

To improve frequency reuse and efficiency, some existing systems access a shared set of frequencies by monitoring the traffic on a pre-specified frequency resource list and accessing only those channels currently not in use. Examples of this include HF‐ALE, MSE, and trunked radios. Another technique involves utilizing a relatively wide channel but sensing the environment within that channel and dynamically “notching out” the occupied portions. An example of a system using this approach is the MUOS UHF SATCOM system.


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7.4.1.2. Full Range Frequency Sensing

To gain significantly more benefit from environmental sensing, systems must be capable of sensing the EME across the full range of their tuning capability. This will be important for improving multi-functionality, flexibility, spectrum protection and for efficiency by contributing to completely autonomous and ad-hoc access to the spectrum.

7.4.1.3. Basic Environmental Categorization

The capability to not only sense the noise floor and occupancy but to determine key elements about how the spectrum is being used is another enabler of various efficiency technologies and techniques. Significant knowledge can be deduced from detecting basic signal attributes such as power, frequency, bandwidth and time. Whether it is for choosing the optimal frequency for operation or the presence of multi-path signals that must be mitigated, categorization enables more precise and intelligent use of the spectrum. For example, the ability to detect and categorize non‐collaborating systems will aid in determining potential frequency sharing opportunities. Categorization also enables a number of secondary missions and capabilities that will enhance operational agility and situational awareness. For these reasons it is a desirable capability to incorporate new SDS.

7.4.1.4. Enhanced Environmental Categorization

Additional benefit may be gained by incorporating even more sophisticated detection and categorization capabilities into a system. Modulation identification, line-of bearing determination, time difference of arrival determination, signal pattern recognition (PRF, broadcast chirps, etc.), signal recording and multiple frequency detection are all examples of enhanced sensing capabilities that can greatly improve a system’s ability to glean more information from the EME. For example, emerging technology in this area includes algorithmically based modulation identification techniques that can enable the determination of potential frequency sharing opportunities and potentially increase frequency reuse. A key factor in improving detection and categorization is processing power. Being able to employ advanced signal detection and categorization schemes (e.g., Choi Williams Distribution, Wagner Ville Distribution) at real time speeds requires significant processor capability. This requires careful management of a processor that must be shared for multiple functions.

7.4.2. Environmental Information Exchange

As with location information, exchanging sensed EME data with other systems and networks can extend and amplify their benefits substantially. Whereas a single device can only detect a limited and localized subset of the EMOE, a whole network of sensors can fully categorize a significant slice of the EME and use that knowledge to optimize any number of attributes. Sharing such data with other systems can enhance situational awareness and survivability across an entire network. Exchanging this data in the Standard Spectrum Resource Format (SSRF) (see the Military Communications and Electronics Board (MCEB) Publication #8) even further enhances the benefits by maximizing the number of systems that can utilize this data.

7.5. State Management SDS than can monitor and manage their operational state, functional configuration and performance

will support many aspects of survivability and agile spectrum operations. Many legacy systems are

only configurable by the operator. This may be necessary for one reason or another but only

systems that can manage their own configurations and operating parameters will score highly in the


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EMS Survivability Scorecard. To enable superior levels of survivability and agile spectrum operations,

systems must be developed that automatically reconfigure themselves to adjust to regulation,

mission, environment or threat.

These capabilities begin with an SDS’ awareness of its own operational state; continues with its

ability to control the various factors that define that state; and peaks with its ability to report or

exchange this data with other systems.

7.5.1. Function/State Awareness

This is the ability to continuously monitor and audit a system’s configuration, performance,

integrity, behavior, and mission posture. This can be accomplished by entirely internal

components or in combination with external instruments and sensors. Additional features

enable the system to alert the operator when any anomaly is detected and/or recommend

remedies.

7.5.2. Automated Function Control

A natural outgrowth of the ability to monitor and audit is to automatically control the various

components and operating parameters of a system. In addition to the spectral attributes

discussed earlier (e.g., power, bandwidth, etc.), survivability features like anti-jam, and

detection reduction can be managed to orchestrate a portion, or the entire operation of, an SDS

and optimize its effectiveness. Just one application of functional controls is one that would

enable the graceful degradation of performance and allow the system to remain mission

effective despite degradation, compromise, or loss of some portions of the system due to

failure, interference or attack. SDS with automated controls can dynamically group and prioritize

functions, and then adjust or turn-off those functions not essential for the current mission.

Automated controls are essential to adapting to changes fast enough to effectively continue to

operate.

7.5.2.1. Adaptive Control

Adaptive controls enable a SDS to employ various modes or configurations that are

hardcoded or remotely controlled, (e.g., decisions made by a network management system)

and can be constantly employed to fine tune performance (e.g., auto squelch). From a

spectrum standpoint, automated and adaptive responses to both internal and external

stimuli offer enormous advantages over slow, manually-intensive control mechanisms and

substantial vulnerability reduction.

7.5.2.2. Cognitive Control

Applying cognitive controls not only allows a SDS to control the function of components and

operating parameters but they can make decisions about the behavior after taking into

account factors like internal state, location, mission and the EME. A prime example of this

type of control is a policy-based control system whereby the functions and behaviors of the

system are controlled or modified by a set of policies or rule sets. From an operational

agility standpoint, cognitive controls enable multiple re-configurations and tailored response

to a myriad of potential situations. For example, policies can drive the device to behave

differently depending upon the location of use, the phase of an operation or the role of the


45

operator. Since policies are configured centrally and distributed remotely, the system or

network can flex and adapt substantially without having to reprogram the device itself. This

high degree of adaptability and flexibility make cognitive control systems highly desirable.

7.5.2.3. Intelligent Control

This type of control employs sophisticated reasoners that incorporate learning behaviors or

even artificial intelligence to enable systems to, not only autonomously react to various

stimuli and situations, but to improve upon those reactions over time by monitoring

effectiveness and making adjustments.

7.5.3. Function/State Data Exchange & Reporting

As with location or sensed information, exchanging mission related data with other systems and

networks can extend and amplify their benefits substantially. This will be a key capability to

enable future electromagnetic battle management systems that will likely consume large

quantities of data from deployed SDS. Exchanging state/configuration data provides tremendous

levels of situational awareness for higher headquarters as well as providing instantaneous

alerting in cases of serious failure or electronic attack.

7.6. Network Management Attributes in this category will primarily affect the relative spectrum efficiency of SDS that carry data networks but also have some minor applicability to other KSAs. Additionally, this attribute is not applicable to the numerous types of SDS that do not transmit or receive packetized data or operate in a network configuration. Some other network management considerations that affect the survivability of a network are addressed in the Cyber Survivability section of the SS-KPP.

Networking efficiency can have a substantial impact on the amount of spectrum a system requires. A previous study14

estimates that, in some types of networks, 90% to 99.9% of the total bandwidth is consumed by networking information or “overhead.” If the frequency band becomes more congested this situation only becomes worse as the number of packet retransmissions skyrockets. Alternative protocols were found to improve this situation by a factor of ten thereby decreasing the amount of spectrum required by a similar factor. Additionally, a tighter integration between network management and spectrum management support systems can significantly improve flexibility, security and responsiveness to operational requirements.

7.6.1. Network Overhead Reduction

Network overhead is the amount of additional information required to maintain network services. The migration from the common TCP/IP wired networks to Mobile Ad-hoc Networks (MANETs) exposes shortcomings and additional requirements relative to traditional wired network protocols. The relative efficiency of the transport control strategy and the network protocol can be key factors in overall vulnerability of a network since relatively low levels of jamming and interference can render their performance unacceptably low.

7.6.1.1. Collision Management

Packet collisions in wireless networks occur when two or more cooperating nodes transmit simultaneously. Various media access control (MAC) protocols attempt to resolve this

14 J. Michael O’Hehir, Advanced Network Protocols Impact on Spectrum Operations, JSC‐CR‐04‐081, Annapolis, MD: DoD JSC, (Oct 04 draft to be published).


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problem in networking referred to as the hidden node. Failure to have an effective MAC protocol will cause the retransmission of unacknowledged packets and reduced throughput. It is therefore beneficial for networked SDS to incorporate a robust MAC protocol strategy.

7.6.1.2. Transport Control

The Transport Control Protocol (TCP) guarantees end‐to‐end packet delivery. This requires an acknowledgement from the destination node for every packet sent. Without that acknowledgement, the packet is retransmitted. Additionally, if packets are acknowledged out of order, the packets will be retransmitted. The efficiency of basic TCP in a wireless multi‐hop environment has been shown to be a dismal 23%. TCP strategy studies15 have shown alternative protocols to be as much as 89% efficient for the same mobile (MANET) environment. It is therefore advantageous for new SDS and networks to employ an efficient transport control strategy.

7.6.2. Topology Management

Maintaining network connectivity in a self‐forming, self‐healing MANET requires robust routing strategies. The amount of network overhead and resulting spectrum bandwidth required to accomplish MANET routing functions varies significantly by protocol strategy and needs to be minimized. Additionally a well-designed physical layout of a network can overcome many of the repercussions of in-band interference.16

7.6.2.1. Network Routing

Wireless networks exhibit much less connection stability than wired networks. This puts an additional strain on the routing protocols used to maintain routing tables (for a table driven strategy) or discovery of routes (in an ad hoc strategy). A previous study17 illustrates the differences in overhead levels amongst various routing strategies and highlights the need to minimize the amount of control packets required to perform routing functions.

7.6.2.2. Directional Routing

The integration of adaptive array antennas into future tactical networks will require tight integration with an optimal network routing strategy. While this increases the amount of protocol complexity, the dramatic improvement in throughput (up to 370%) justifies this tradeoff and can be used to reduce the amount of spectrum required. Overall security and system survivability is greatly enhanced by the flexibility and low detectability these technologies provide. Future wireless networks that employ adaptive array antennas must leverage spatial domain processing into their network routing and MAC protocol strategies.

7.6.3. Access Priority

The availability of spectrum to support any military operation will always have bandwidth limitations; particularly in the most heavily subscribed bands. One strategy to handle bandwidth constraints or even just general congestion is to assign priority or quality of service restrictions; this can be to missions, networks, devices, or even down to individual messages and packets. Systems that employ priority assignment strategies are inherently more efficient and effective

15 ibid 16 “Dynamic congestion detection and control routing in ad hoc networks”: T. Senthilkumaran & V Sankaranarayanan ,2013, http://www.sciencedirect.com/science/article/pii/S1319157812000195 17 “Method for reducing routing overhead for mobile Ad Hoc network”: Wei-Chih Ting & Jui-Wen Chen, 2010 http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5633159&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5633159

http://www.sciencedirect.com/science/article/pii/S1319157812000195

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5633159&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5633159

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5633159&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5633159


47

and should be encouraged. Additionally, the interface between network management and spectrum management support systems must provide a seamless provisioning of frequency resources. The more automated and precise the coupling of these two functions the better.

7.6.4. Quality of Service

For networks to achieve a desired level of end‐to‐end quality of service (QoS) they will have to consider the spectrum bandwidth limitations of each and every traversed link to accurately determine the best path for guaranteed delivery. Alternatives to the Open Shortest Path First (OSPF) protocol may be required due to bandwidth limitations. The OSPF protocol is one form of QoS strategy determined by the number of nodes traversed. In wireless networks, the shortest path may not have the effective bandwidth to support the required QoS due to link interference. The most desirable networked SDS should integrate bandwidth availability into their QoS routing schemes. These considerations reinforce the benefits of other adaptation schemes to produce more stable paths for data transmissions.

7.6.5. Link Monitoring

This is sometimes referred to Channel State awareness. Certain techniques allow systems to monitor a link for evidence of interference or jamming. Some require monitoring at both ends of the link and a few can infer interference from only one end. Still others may rely on separate spectrum monitoring to provide situational awareness and secondary indications of link quality by frequently sampling the EME in the area, QoS routing schemes that account for the quality of the link will significantly improve network performance and reduce overall system vulnerability.

7.6.6. Spectrum Management Integration

The speed at which spectrum management can be accomplished has a direct effect on flexibility, survivability and the overall efficiency achieved. Any process that requires human intervention causes delays in adaptation; therefore, spectral attributes are squandered. The requirement to use the spectrum through the provisioning of frequency resources should be seamless and as automated as possible. Therefore, SDS or networks that can automatically access spectrum management systems (e.g., SPEED, SXXI) for spectrum resources will have advantages over those that do not. Those that incorporate their own spectrum management capabilities will be more effective still. Even further on the effectiveness scale, systems that employ policy based spectrum management techniques will be able to instantaneously determine their own optimal and legal spectrum resources and thus achieve a high degree of efficiency and flexibility.

7.7. Data Management The exponential growth in data levels is one of the primary drivers of spectrum demand and will continue to be so for the foreseeable future. The volume of data passing over a wireless link or network has a direct impact on spectrum demand and thus impacts efficiency. Therefore it is paramount that technologies and strategies be employed that reduce the amount of data required to be transmitted as much as practical. It should also be noted that the spectrum dependent systems are usually not the primary culprits when it comes to data overload; the data source-systems or the applications that ride them are. However, SDS can significantly reduce the problem. While many technologies and strategies exist to accomplish data management, here are several of the most effective. Also included is one that must be used for security but should not be overused.

7.7.1. Filtering

Trying to transport vast amounts of raw and unfiltered data over a communication’s link is

wildly inefficient and drives up costs along the entire information chain. Filtering out


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unnecessary, duplicative or corrupted data represents low hanging fruit in the struggle against

data overload and should be employed at every opportunity.

7.7.2. Onboard processing

Processing raw data at the source is another proven strategy for reducing demand. Applications

that sort, analyze, correlate and fuse raw data can not only dramatically reduce the volume of

data needed to be transported but they can accelerate the process of making the data useful for

decision making.

7.7.3. Data Throttling

Also known as data metering, this technique involves managing traffic flows so that the maximum amount of data can be transported over a given time period. While somewhat related to Quality of Service considerations described in factor 7.6.4, this strategy focuses on managing a link, or network of links, according to data demands vs bandwidth availability. Priority scheduling, load balancing, store & dump schemes and dynamic data metering are all examples of this technique.

7.7.2. Data Compression

This is a common and proven technique for managing data demand. Applications exist that can

compress data by factors of ten or more with little loss of fidelity. Data compression techniques

often lead to losses of data so they cannot be applied to all missions and all cases. However,

most applications suffer minimal losses and can achieve significant reduction in overall data

volumes.

7.7.3. Encryption

From a spectrum perspective, encryption is a negative or “necessary evil" because each level of

encryption adds between 3% and 6% of overhead to the data stream. Due to the added security

however, this is a worthwhile price to pay. What is often unnecessary however is double and

even triple encryption. If an encrypted signal is "tunneled" through an already encrypted link

(e.g., tunneling through a SIPRNet data line which already employs Type 1 encryption) the

overhead is cumulative and begins to significantly drive up overhead for little or no

improvement in security. Use of additional encryption layers should only be employed where

absolutely required by established policy (e.g., Segregation of SCI networks).

7.7.4. Data Error Detection & Correction

The general idea for achieving error detection and correction is to add some redundancy (i.e.,

some extra data) to a message, which receivers can use to check consistency of the delivered

message, and to recover data determined to be corrupted or missing. Error-detection

techniques like using check-sums, parity bits and cyclic redundancy checks are common

methods of detecting date transmission errors. Such schemes are often combined with

Automatic Repeat Request (ARQ) methods to provide for the retransmission of corrupted or

missing data.

Other schemes such as Forward Error Correction (FEC) add additional data to a message so that

the receiver can reliably reconstruct corrupted data stings without the need for retransmission

(up to the limits of the particular FEC method chosen). Applications that require low latency


49

(such as voice conversations) or that automatically delete the data immediately (Television

broadcasting) or that do not utilize a return channel cannot rely on ARQ; they must use FEC

schemes. Such schemes are commonly used to improve the reliability of data links and therefore

support the survivability of the system. However, some schemes can significantly increase the

amount of overhead data a system or network must handle and thus reduce overall efficiency.

Such factors must be balanced in the overall design.

7.7.5. Data Recording

This is an underappreciated capability that should be included whenever practical and

affordable. The vast majority of operational systems do not include the capability to record

operational data which precludes a number of potential benefits. Sensed EMOE data in

particular is highly useful for forensic analysis of EMI events, to assess and adversary’s

capabilities and is critical for the rapid reprogramming of ES/EA/EP systems to counter evolving

threats. Other types of operational system data can be very useful for analyzing system

performance.


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Appendix A - Guidance for endorsement reviewers

The EMS Survivability guidelines are designed to be more easily enforced. This is because they include

much clearer instructions on what is expected to comply and where related items should be

documented in the JCIDS prescribed documents. Reviewers of such documents should use the guidance

below to quickly and effectively evaluate whether the Program Offices are complying with the letter and

spirit of EMS Survivability.

General Guidance: The EMS Survivability process is designed to ensure that proper consideration of

EMS threats, vulnerabilities and potential electromagnetic operational environments (EMOE) in which

our systems/equipment are intended to operate prior to making design decisions and specifying system

survivability requirements. Secondly it is to ensure that the broad gamut of EMS Survivability related

issues are properly addressed during the requirements development process. These goals will be

achieved through proper threat and risk assessments and by complying with the requirements of the

spectrum Key System Attributes (KSA) so these are the areas to focus on during a review. While it is

often difficult to judge a submission on its technical validity, the Program Offices should include

sufficient evidence to establish that they understand EMS Survivability requirements and are actively

considering all relevant EMS issues in their requirements and design specifications.

Specific Guidance: Review the following sections of all specified JCIDS submission.

Section 1 – Operational Context – Review to seek evidence for whether the system is EMS

Reliant and therefore must comply with the EMS Survivability process.

Is there an acknowledgement that the system is spectrum dependent? Does it include core

functions like Electronic Attack, wireless communications, sensing, radio-detection, ECM,

signal collection, etc.

Does it describe any EMS related enabling capabilities? E.g., Will it need spectrum

management support? Will it require network management services for wireless networks it

connects to?

Will it require EMS Related Intelligence Support Activities? E.g., TACELINT or SIGINT

support? Electronic Support (ES)?

Section 2: Threat Summary – Review to seek evidence that EMS threats have been analyzed and

taken into proper consideration

For an ICD – does it indicate whether a System Threat Analysis has been requested?

For a CDD or CPD – Does the threat analysis include EMS or non-kinetic threats? Does it

mention any specific types of EMS threats?

Is a link to the STAR provided or is one attached to the submission?

o Does the STAR address the four key EMS questions listed in section 6.2.1? (normally

found in sections IV[Threat Environment] or V[System Specific Threats])

System Description – Does it indicate whether the system is likely to be reliant upon the EMS.


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Section 5 - Development Performance Attributes: Under SS KPP is there an EMS Survivability

sub-section and does it include the following elements?

o For an ICD –

Does it include the score from the initial EMS Survivability scorecard?

Are there any EMS related operational requirements stated?

Are there any Waivers listed? If so, do the justifications seem reasonable?

o For a CDD, CPD or ISP –

Is the Risk Category stated? Does the explanation for it seem reasonable?

For a platform or SoS, are the hosted SDS listed and compliance of each with the

EMS Survivability requirements summarized in the CPD?

Does it include the scores from the EMS Survivability Scorecard?

The competed scorecard questionnaire is valuable to review if any of

the category scores are low or there appears to be a disconnect

between the threat category and the extent of mitigating requirements

listed. Completed scorecards for all programs may be obtained from

the Scorecard website at ( ???)

If no score is listed, does it include statements to address each of the 5

EMS Survivability attributes?

Are there specific EMS Survivability requirements listed?

Do these seem commensurate in scope and detail with the stated threat

category?

Often EMS related requirements are stated in other KPP sub-paragraphs

so it is useful to scan through these to see if any exist and if they

support the EMS Survivability attributes.

While not mandatory, if there are any performance criteria they should be listed

here as well. Do these seem reasonable? Are they at least similar to any of the

prescribed performance criteria from Section 9 of this guidebook?

Section 7 – Spectrum Requirements: Review

o Ensure that the need for E3/EMS compliance is stated.

o If the system is RF dependent, does it specifically require a Spectrum Supportability Risk

Assessment (SSRA) be completed?


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Appendix B –Completing the EMS Survivability Scorecard During each of the first three phases of system development depicted in figure 5 the program office

must complete a tailored series of questions to determine the EMS Survivability score. Questions in the

Material Solutions Analysis phase are somewhat general and geared towards ensuring that the required

steps are being followed and EMS factors are being adequately considered. Questions in the Technology

Maturation and Risk Reduction phase are more targeted and geared towards ensuring that known risks

are being properly evaluated and factored within the design trade-space. Questions in the Engineering

and Manufacturing Development phase are much more technology specific and geared towards

evaluating the chosen technologies, strategies, or techniques against the KSA criteria.

The EMS Survivability Scorecard tool is accessible at: >> Place link here with any administrative remarks

about setting up an account or tips on accessing the tool<<

The questionnaire does not need to be completed at any single session but may be accessed and

updated as many times as needed up until the final submit button is selected. This allows answers to be

changed as new requirements are developed and/or changes to the system design are made. Once the

questionnaire for a particular phase is completed it will be recorded and stored for future reference or

access. Completed questionnaire will also be available to those with appropriate access (e.g., MDA, SS

KPP Endorsement review team, etc). Scores for each KSA shall be listed in the appropriate JCIDS

document in the EMS Survivability section. The complete scorecard with answers shall be attached to

the document as well.

All systems will be evaluated using an appropriate combination of the previously described criteria (see

section 7). However, questions are tailored by system type. Only SDS that operate in the RF portion of

the spectrum will be asked questions reflecting KSAs 2 through 5. Also, the criteria do not apply equally

to all types of SDS and some won’t apply at all. For example, only a few criteria might apply to a DE

Weapon system; similarly, only ROs/PMs for a SoS, or networked SDS need be concerned with the

Network Management criteria. Again, the questions will be somewhat tailored by category of system

This is also why the scorecard provides different threshold scores for each system type.

Scoring: Scorecard questions are crafted to yield specific answers. Most can be answered with a simple

Yes/No, True/False or with a choice from a pull down menu. Most answers to the scorecard

questionnaire have an associated point score. As the survey questions are answered the survey tool

automatically tallies the scores in the appropriate KSA field. If the system incorporates or utilizes a

particular technology, strategy or technique listed, the point value of that item is added to its scores for

the appropriate KSAs. Threshold scores have been determined such that, by incorporating a modicum

of the recommended technologies, strategies or techniques into the system design, the system will be

able to achieve the threshold score for each KSA. Threshold scores are intended to trigger self-

examination by the RO/PM/MATDEV of the system’s requirements, risks and design tradeoffs. Threshold

scores are also designed to trigger greater scrutiny of the system’s design by approving officials.

Program offices of systems that score below their threshold range for a particular KSA will be required

to demonstrate to the MDA and the Protection FCB why greater investment in EMS technologies,

strategies, features, etc. is unnecessary or infeasible.


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Appendix D - Prescribed Performance Criteria Performance criteria can be highly problematic to prescribe. While employing them can be useful for

achieving the end-state envisioned by a system’s designers, they must be carefully crafted and specified

with well understood constraints and conditions before the system is tested to ensure the results are

valid. Otherwise they can be all too easy to manipulate and contort so as to achieve “predetermined” or

inadequate threshold values which do not reflect the original intent. This in turn would undermine the

purpose of the system survivability KPP. By their very nature the EMS Survivability attributes do not

lend themselves to any one-size-fits all or universal performance criteria. There are too many variables

and unique conditions to satisfy for such performance criteria to be valid across so many diverse

systems. Therefore no performance criteria are “prescribed” as a requirement for EMS Survivability.

However, their use is recommended when and where appropriate.

If a requirements officer, operational sponsor or program manager wishes to specify a performance

parameter (KPP, KSA or APA) to achieve a desired level of EMS Survivability, s/he should first consult this

list of recommended performance criteria for possible candidates. Each has been chosen to provide a

viable measure or indicator of performance for a desired EMS Survivability Key System Attribute. While

there are certainly many other potential performance measures that could be applied, these should be

reviewed first before developing completely different and unique ones. Each of these has been

reviewed for efficacy, utility and applicability and will help ensure an improved level of survivability for

the system if properly employed. By choosing from this prescribed list there is a far greater chance that

results can be honestly compared to those of similar systems and that a useful requirement is being

added to a system’s design.

The majority of these suggested criteria apply to systems operating in the RF portions of the spectrum

(From ELF to MMW or 3 Hz to 275 GHz). These systems are subject to all five of the EMS Survivability

KSAs. However several have been developed that apply to platforms and SoS or that apply to the

Spectrum Protection criteria in general. There are no suggested criteria here for systems that merely

have electronics that might be susceptible to EM effects. Such criteria as well as testing procedures are

already specified in DoDI 3222.03P

Modification to these criteria may be necessary to adequately meet a desired end-state as long as the

conditions and constraints are well understood and agreed to by the appropriate stakeholders. Some

systems are so unique that they defy any attempt to apply performance measures. In these cases the

RO/PM/MATDEV should consider specifying the use of observable functional criteria instead of

measureable performance criteria. For example, if the desire is to reduce total life-cycle cost and

complexity across a family of vehicles one can specify that each model to be developed shall utilize the

same engine. This is far easier than specifying that each engine must develop X horsepower, using Y

Ft/lbs of torque, and displacing z cubic centimeters of volume. For a more germane example the RO

may find it more effective to specify that the system employs adaptive power management schemas to

conserve power, improve spectrum efficiency and reduce detectability rather than specify a criterion for

each of these separate attributes which would be difficult to measure.


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When a performance parameter is chosen it shall be listed in the EMS Survivability Section of the CDD

and/or CPD.

Table 1 - Suggested Performance Criteria

Type of System

Attribute Criteria Choices Metric or Indicator Options

Any specified conditions or constraints

Notes on applicability

Radio Frequency Spectrum

Dependent Systems (RF-SDS)

1. Efficiency

1.1. Relative Spectrum Efficiency (RSE)

To calculate RSE one first needs to calculate the Spectrum Utilization Factor (SUF) and then the Spectrum Utilization Efficiency (SUE)

The measure of spectrum utilization – SUF or simply U, is defined to be the product of the frequency bandwidth, the geometric (geographic) space, and the time denied to other potential users: U = B · S · T where B : frequency bandwidth S : geometric space (usually area) and T : time. SUE can be expressed by a complex criterion: SUE = {M, U} = {M, B · S · T} where: M: useful effect obtained with the aid of the comm system in question U: spectrum utilization Factor for that system. If necessary, this complex spectrum efficiency indicator may be reduced to a simple indicator: the ratio of useful effect to spectrum utilization factor: SUE =

The geometric space of interest may also be a volume, a line (e.g. the geostationary orbit), or an angular sector around a point. The measure of spectrum may be computed by multiplication of a bandwidth bounding the emission (e.g. occupied bandwidth) and its interference area, or may take into account the actual shape of the power spectrum density of the emission and the antenna radiation characteristics. The amount of space occupied depends on the spectral power density. For many applications, the

*Defined by the ITU in SM.1046-2, May 2006: “Definitions of spectrum use & efficiency” *Some examples of RSE calculations are presented in Annex 2 and in Chapter 8 of the National Spectrum Management Handbook (Geneva, 2005) *Efficiency Attributes are not applicable to EA systems. *Any comparison of spectrum efficiencies should be performed only between similar types of radio systems providing identical radiocommunication services.


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𝑀

𝑈=

𝑀

𝐵 · 𝑆 · 𝑇

Finally RSE may be calculated as a ratio of system being compared SUEa and the system used for reference SUEref

𝑅𝑆𝐸 = 𝑆𝑈𝐸𝑎

𝑆𝑈𝐸𝑟𝑒𝑓

Candidates for SUEref are -The system being replaced -A similar system in wide use that can be easily defined and understood. The RSE will be a positive number with values ranging between zero and infinity. If the standard system is chosen to be the most theoretically efficient system, the RSE will typically range between zero and one.

dimension of time can be ignored, because the service operates continuously. But in some services, for example, broadcast and single channel mobile, the time factor is important to sharing and all three factors should be considered simultaneously, and optimized.

1.2. Comparable system bandwidth

What is the total bandwidth used for several key modes of operation and how does this compare to that of a similar system performing the same test/function? Can the system perform the mission just as effectively using no more than the same amount of spectrum?

System configuration, target RCS & characteristics and EME conditions must be tightly controlled for testing this measure to be valid. Validity also depends upon the fairness of the comparison. Must ensure that one apple is only

Recommended criteria for Radiodetermination class devices such as RADARs.


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being compared to another apple.

2. Adaptability

2.1. RF Management

Parameter control - # of parameters that can be automatically controlled (e.g., Power, Bandwidth, data rate, Adaptive antenna patterns, etc)

System must be able to change such parameters dynamically to optimize performance for the particular EMOE or mission.

Parameter control accuracy: Of those parameters that can be automatically controlled (e.g., Power, freq hop rate, bandwidth, etc.), is each control implemented accurately? This measures the error rate and degree of error that an automated system can execute. E.g., If the system logic calls for 10 watts of power to the transmitter, is 10 watts of power actually being transmitted?

Some parameters must be bench tested under strict conditions and configurations. Others must be tested in an anechoic test chamber.

2.2. Geographic Awareness

Performance dependency -Does the system optimize any of its parameters based upon awareness of location? Which parameters and how frequently does this optimization occur?

Can be an internal or external source of location info.

Functional dependency – How many system functions or secondary applications depend upon awareness of location? Is there a


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secondary source of location data? How often does the location data need to be refreshed?

2.3. Environmental Awareness

Performance Dependency - Does the system optimize the setting of its parameters based upon awareness of the EMOE? Which parameters and how frequently does this optimization occur?

Must pre-define which parameters will be observed. Ideally, all parameters that a system can dynamically change should be observed.

Functional Dependency – How many functions or secondary applications depend upon awareness of the EMOE?

2.4. State Management

Parameter monitoring accuracy – Does the system detect the same operating parameter levels as those detected by test equipment?

May be established through software emulation but preferably via bench testing using the latest configuration.

Automated functional control – Does the system automatically “react” as expected when a monitored anomaly occurs?

May be established through software emulation but preferably via bench testing using the latest configuration.

2.5 Frequency Hop rate.

Usually defined as the number of frequency changes per second.

3. Spectrum Access

Flexibility

3.1. Cooperative ability

Does jamming performance improve if the system coordinates its operation with other SDS?

System configuration and EME conditions must be tightly controlled for testing this

Recommended criteria for EA systems


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measure to be valid. Results measured at the target’s receiver.

3.2. Sharing etiquette

Under stable and controlled conditions, how often does the system cause unacceptable interference with another system that is also trying to utilize (share) the same channel or band of spectrum. This is a measure of correct application of any particular sharing protocol.

If the system is capable of more than one method of sharing, this test must be run separately for each method. System configuration and EME conditions must be tightly controlled for testing for such EMI to be valid. See MIL-STD-464C for guidance on how to control both of these factors.

3.3. Multi-band operations

Bit-Error-Rate – When a signal is divided up amongst two or more separated bands, how does the performance and throughput compare to that of the same signal utilizing a single contiguous band of the same total width.

System configuration and EME conditions must be tightly controlled for testing for BER to be valid. See MIL-STD-464C for guidance on how to control both of these factors.

While this example applies to duplex digital communications, a similar performance comparison could be made for other types of equipment.

3.4. Wide Tuning Range

Tuning Range Comparison – How does the tuning range of the system compare with equivalent systems already deployed?

Tuning Range viability – can the system perform all functions and capabilities across


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the entire tuning range?

4. Spectrum Protection

4.1. Bit Error Rate

Bit-Error-Rate can be used as a rough proxy for link performance under various levels of EMI. Using pre-selected levels of EMI to represent a lightly, moderately and heavily congested EMI, the BER can be used to gauge the system’s QoS and resilience in such environments.

System configuration and EME conditions must be tightly controlled for testing this measure to be valid. See MIL-STD-464C for guidance on how to control both of these factors.

Primarily for duplex digital comms

4.2. Emissions Control

Spurious emissions: Does the system meet the requirements for EMCON as defined by MIL-STD-461 C/D?

EMCON Centralization: Can EMCON be imposed centrally? Is operation of the system purely manually controlled, autonomously (self) controlled, platform controlled (integrated with the platform’s decision making for all emitters) or network controlled for a more force-wide level of emissions control?

4.3. Aggregate countermeasure benefit

Test the change in QoS factors (e.g., BER, Throughput) as each available countermeasure is selected on. Then re-test using various combinations of countermeasures to try to determine the aggregate benefit.

System configuration and EME conditions must be tightly controlled for testing this measure to be valid. See MIL-STD-464C for guidance on how to control both of these factors.


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4.4. System Performance in contested environments

-Do the primary functions of the system maintain at least the threshold level of performance when subjected to conditions representing the harshest EMS environment identified in the STAR? -The term "performance" is system specific. For example a RADAR's primary function might be target detection. Under optimal conditions it might be capable of detecting a standard test object (RCS of 1m2) at 220 NM. If all other variables are held constant but the system is subjected to the harshest EMS environment, it should be able to detect that same object at 50 NM (Threshold) or 75 NM (Objective).

-Must keep all non-EME variables and conditions consistent. -EMI type must be specified: either coherent or non-coherent. If both, the tests must be run separately for each.

5. Multi-Functionality

5.1. # of systems replaced

A straightforward measure of how many systems an operator has to utilize to accomplish the same missions both before and after the new system is deployed.

Only applicable if the system is truly being designed to replace another one.

5.2. Functional comparison

Tabulate the major functions of the system and compare to a equivalent/similar system or the one it is replacing.

Validity depends upon the fairness of the comparison. What is considered a major function


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needs to be defined before the count is made. 2 or more comparisons is recommended

5.3. SWaP Comparison

Measure of the space occupied, weight and or power consumed by the new system as compared to a similar system or the system(s) it is replacing.

Validity depends upon the fairness of the comparison. Must ensure that one apple is only being compared to another apple.

Non RF systems to

include platforms

and Systems-of -Systems

6. Spectrum Protection

6.1. Radar Cross Section (RCS)

RCS is the measure of a target's ability to reflect radar signals in the direction of the radar receiver. Usually measured in meters squared (m2). To be useful RCS should be measured against a variety of radars using varying modes under differing operating conditions.

Validity depends upon controlling the operating parameters of the illuminating RADAR, the aspect and range to the target and environmental conditions.

*Applies primarily to platforms

6.2. Emissions Control (EMCON)

Spurious emissions: Does the system meet the requirements for EMCON as defined by MIL-STD-461 C/D?

May not apply to platforms with multiple SDS

EMCON Centralization: Can EMCON be imposed centrally? Is operation of the system purely manually controlled, autonomously (self) controlled, platform controlled (integrated with the platform’s decision making for all emitters) or network controlled for a more force-wide level of emissions control?

*Applies to individual SDS as well as platforms & SoS.


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6.3. Level of CM integration

Are countermeasures controlled and activated purely manually, autonomously (Self) controlled, Platform controlled (integrated with the platform’s decision making for employing countermeasures) or can they be networked with the countermeasures on other platforms for a more force-wide level of countermeasure employment and mutual protection.


6.4. EMS Signature monitoring

This is a measure of how well a platform can assure that it is not emitting any unintended energy. Does the platform have a means to independently monitor the emissions of all SDS onboard? How effectively does it alert the operator? If so, how accurately/consistently does it detect such emissions?


6.5. EMOE Monitoring

This is a measure of how much benefit is derived from EMOE monitoring. How well does the monitoring system alert the operator when EMI conditions are detected for any of the onboard SDS? Does the monitoring system integrate with other

*Applies to platforms and SoS.


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hosted SDS for spectrum access decision making? Does the data get recorded for playback and analyses? Does the system network with other platforms or SoS to share EMOE events and conditions. If so, how well does it perform at this function?

This is a measure of the sophistication of EMOE monitoring. Can the SDS detect basic energy levels on a tuned frequency? Can it detect and determine any specified parameters of the received signal? Can it determine statistical properties of the received signal? Can it determine waveforms? Can it geolocate or determine a line-of-bearing to a received signal? Can it record information about the received signal? Another potential measure is how accurately the device measures the parameters of the received signal.

Graceful Degradation

Does the system provide the prescribed indicators and warnings for needed operator or system interventions to preserve minimum


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functionality and performance levels (measures Anomaly Detection & Warning).

Does the system recede to the programmed “safe mode” when critical anomalies are detected? When the fault or anomaly is cleared does the system returns to its normal operating mode?

IR/VIS and UV Signatures

One method is to measure the emissivity of a system or component by using a spectrometer. Select the exact wavelengths to me measured (IR is a broad range, visible less so) and specify the mode of operation (say a motor at normal cruise power settings) and then set threshold and objective limits on how much IR energy the system can emit. Ideally these limits should be based upon the sensitivity of adversary threat seekers or sensors at relevant wavelengths and in typical environmental conditions.

Validity depends upon controlling the testing variables like the operation of the target system, aspect of the target, background temperature and external sources of IR energy (these might corrupt the measurements).as well as the sensitivity and selectivity of the Spectrometer used to make the measurements.

In some cases such as a SoS the combined signature of all the components may be more significant than the signature of just one.


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Appendix E – Sample Requirements Statements

Well defined and specific requirements statements are critical for ensuring that any system under

development meets the end user needs and expectations. Listed below are sample requirements

statements that can be used to help the RO/PM/MATDEV to specify the attributes and features

necessary to produce a survivable design.

Each of these sample requirements reflect a specific attribute and criteria discussed in Section 7 of this

guidebook and each references the specific section number from which the requirement is derived so

that additional detail and context can be quickly found if desired. This list is neither exhaustive nor all-

inclusive but provides a solid starting point for developing requirements that will not only demonstrate

compliance with the EMS Survivability process but lead to more survivable and effective system designs.

Not all systems need to be exquisitely adaptable, flexible, efficient, resilient and multi-functional. It is

highly recommended that these samples be analyzed and used selectively based upon their applicability

to the desired capability. These are meant to be plagiarized, adapted and parsed to meet the specific

needs of any program. They are also intended to inspire, generate further ideas and provoke

discussions about the level of EMS survivability that is truly necessary and desired.

The first table lists sample high-level operational requirements that are appropriate for an ICD. Since

ICDs are required to be brief and concise and since detailed technical requirements have usually not

been developed by this point, these samples offer a solid starting point for Requirements Officers. The

requirements in Table 4 are more specific and therefore appropriate for CDDs, CPDs and ISPs.

Table 2 – Sample Operational Requirements for ICDs

Applicable section Example Requirement

For the Threat Summary section

The STAR will specifically address EMS threat considerations to include: (1) The capacity and technical ability of likely adversaries to deny, degrade or disrupt this system's effectiveness; (2) The capacity and technical ability of likely adversaries to detect, surveil, classify and target the emissions of this system; (3) the ability and sophistication of likely adversaries to effectively employ Electronic Warfare (EP, ES, EA) against this system; (4) The likely adversaries’ ability to effectively protect its own systems against attacks from this system/SoS/platform (Only applicable if the system has an EA function).

For the SS KPP, EMS Component subsection.

It is anticipated that this system will be required to operate in highly/moderately congested and contested EM environments. Accordingly the system shall incorporate high/moderate levels of EMS Survivability features in order to achieve mission assurance.

The system shall employ a robust mix of threat warning as well as active and passive countermeasures to avoid, thwart or mitigate the effects of an adversary's Electronic Attacks

Since this platform will host many EMS reliant systems, appropriate requirements will be developed for them so that they contribute to the entire platform's desired level of EMS Survivability.


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The entire spectrum "signature" of the system shall be measured (preferably by an independent lab), modelled and appropriately diagrammed.

Specific EMS threat scenarios will be developed or considered to inform the development of more detailed EMS Survivability requirements and performance measures.

Table 3 - Sample Requirements Statements

Ref # Criteria Example Criteria Guidebook Reference

Spectrum Protection 7.1

SP 1

MIL-Stds

The System shall meet or exceed MIL-STD-464C requirements for reducing environmental effects.

7.1.1.1

SP 2 The System shall meet or exceed MIL-STD-461F requirements for controlling Electromagnetic Interference.

7.1.1.1

SP 3 Filtering Robust combinations of analog and digital filtering techniques shall be employed to reduce system susceptibility to EMI.

7.1.1.1.2

SP 4

Graceful Degradation

The system shall incorporate hardware and software features to enable the system to gracefully degrade when overstressed by external EMI effects.

7.1.2

SP 5 The system shall provide appropriate alerts to the operator when in a degraded mode.

7.1.2

SP 6 The developer shall establish the threshold levels of performance that the system must be able to maintain when operating in a degraded or safe mode. (a.k.a. "Operational Thin Line")

7.1.2

SP 7

War Reserve Modes

The developer shall identify specific operating modes to be strictly reserved for wartime employment.

7.1.3

SP 8

The developer shall design and test specific operating modes that can maintain useful (level and/or type should be specified for each particular system) functionality in a highly contested EMOE (Defined as the maximum field strength levels determined during the system threat assessment.)

7.1.3

SP 9 The system shall include automated protections against the unplanned, unauthorized or accidental employment of any wartime reserve modes.

7.1.3

SP 10 Countermeasures The system shall be able to monitor and provide the status for the operator to know whenever the system is transmitting.

7.1.4.1.1


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SP 11 The system shall be configured to restrict any and all transmissions (execute EMCON) via direct operator selection, network control or automated self-determination.

7.1.4.1.1

SP 12 The system shall employ an integrated mix of countermeasures designed to defeat all EMS threats identified in the system threat analysis report (STAR).

7.1.4

SP 13

The system shall be able determine the likelihood (or perhaps level of confidence) of jamming (incoherent) activity on the frequency of operation based upon either information from an organic sensor or from offboard detection systems.

7.1.4.1.3

SP 14 The system shall alert the operator whenever disruptive levels of EMI are detected (e.g., during jamming activity).

7.1.4.1.3

SP 15 The system shall employ automated mitigation strategies to counter disruptive levels of EMI (e.g., for jamming).

7.1.4.1.3

SP 16

The integrated defensive countermeasures system shall record operational data ( sensed EMS data, critical systems performance data, etc.) sufficient to replay and analyze for system performance improvement.

7.1.4.2.1

SP 17 The IR, Visible and UV signatures of this platform shall be modelled & diagrammed.

RF Management 7.2

RF 1 Frequency

Tuning Range The system shall have as wide a frequency operating range (tuning range) as its various components will allow.

7.2.1.1

RF 2

Frequency Sharing

They system shall incorporate the ability to automatically coordinate with other SDS within its network to dynamically manage spectrum access and allocation

7.2.1.2

RF 3 The system shall be able to calculate the optimal signal propagation paths given factors such as frequency, radiated power, altitude, orientation, geographic position and terrain data.

7.2.1.2

RF 4 The System shall be able to dynamically switch frequencies (Hop) at least X times per second in a pre-programmed, pseudorandom sequence (or other unpredictable manner TBD).

7.2.1.2

RF 5

Bandwidth Management

The system shall include the option to dynamically manage its transmission bandwidth to match the mission requirements.

7.2.1

RF 6 The system shall comply with MIL-STD 461 for unintentional emissions.

7.2.1.2

RF 7 The system shall dynamically manage the signal modulation to optimize capability for mission, function and the EMOE.

7.2.3.1


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RF 8 The system shall be capable of employing carrier aggregation (virtual channels composed of non-contiguous bands of spectrum) when contiguous spectrum is insufficient to meet mission needs.

7.2.3.1.2

RF 9 Power

Management

The System shall be capable of dynamically managing the power output of its transmitter to minimum level necessary to accomplish the mission.

7.2.4

RF 10 The system shall be able to dynamically manage the power output for every pulse transmitted

7.2.4

RF 11

Antenna Management

The system shall incorporate adaptive antennas that can dynamically steer a signal and "listen" in a desired direction (or sector).

7.2.5.1

RF 12 The system shall incorporate adaptive antennas that can dynamically and simultaneously steer, multiple, separate signals in multiple desired directions (or sectors).

7.2.5.1

RF 13 The system shall incorporate adaptive antennas and receivers that can dynamically filter out or "null" signals coming from any designated direction, elevation or sector.

7.2.5.1

RF 14 The system shall be able to dynamically "notch out" or "null" specific frequencies or frequency ranges.

7.2.5.1

RF 15 The antenna system shall maintain at least a X signal to noise ratio over the transceiver's entire tuning range

7.2.5.3

RF

Geographic Awareness 7.3

GA 1

Location Awareness

The system shall be able to incorporate location/positioning data into its functional logic for managing operating parameters.

7.3.1

GA 2 The system shall have access to positioning data (either organic or provided by an external source) accurate to within x meters.

7.3.1

GA 3 The system shall incorporate terrain data (accurate to within x meters) into it functional logic for managing operating parameters.

7.3.1

GA 4 The system shall have access to at least two sources of positioning and timing data for redundancy.

7.3.1

GA 5 Orientation Awareness

The system shall be able to automatically determine antenna orientation to within X degrees or azimuth and x degrees of elevation.

7.3.2

GA 6 Location Information

Exchange

The system shall be able to report self-location to the network management system either automatically or on command.

7.3.3

GA 7 The system shall be able to share location data with other nodes in the network.

7.3.3


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GA 8 The systems shall be able include Positioning, Navigation and Timing (PNT) information in its data reporting.

7.3.3

GA 9 The system shall be able to record up to X-minutes of received signal data.

7.3.3

GA

Environmental Awareness 7.4

EA 1 Limited Frequency

Sensing

The system shall be able to determine the noise floor (Average ambient background EM energy that does not include the signals of interest) of any frequency band within its tuning range.

7.4.1.1

EA 2 The system shall be able to detect received electromagnetic energy across the full range of its tuning capability.

7.4.1.1

EA 3 Full Range Frequency

Sensing

The system shall be able to detect whether any particular frequency band within its tuning range is "occupied" by some other user.

7.4.1.2

EA 4 Basic

Environmental Categorization

The system shall be able to determine from received signals such attributes as (power, bandwidth, frequency, time, etc.) (*This list of attribute should be tailored to suit the needs of the system)

7.4.1.3

EA 5

Enhanced Environmental Categorization

The system shall be able determine such received signal attributes as Modulation type, line-of bearing, time difference of arrival, signal pattern recognition (PRF, broadcast chirps, etc.), multiple frequencies, etc.) (*This list of attribute should be tailored to suit the needs of the system)

7.4.1.4

EA 6 The system shall be able record up to X minutes of received signal data.

7.4.1.4

EA 7 The system shall be capable of categorizing detected signals. 7.4.1.4

EA 8 Environmental

Information Exchange

The systems shall be able to include EMOE data in its data reporting (The specific types of EMOE data required may need to be specified).

7.4.5

EA

State Awareness 7.5

SA 1 Function/State

awareness

The system shall continuously monitor its own configuration, integrity, performance, behavior, and mission posture.

7.5.1

SA 2 The system shall audit its own configuration, integrity, performance, behavior, and mission posture.

7.5.1


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SA 3 The system shall be able to display its current configuration, integrity, performance, behavior and mission posture.

7.5.1

SA 4 The system shall be able to alert the operator of any anomalies to its configuration, integrity, performance, behavior and mission posture.

7.5.1

SA 5 The system shall be incorporate performance trend analysis. 7.5.1

SA 6

Adaptive Control

The system shall be able to change all operating parameters automatically (as opposed to or in addition to manually) (or a specified subset of operating parameters).

7.5.2.1

SA 7 The system shall employ pre-programmed responses to internal system stimuli (as specified or TBD) (e.g., internal fault detected, Low battery signal, etc.)

7.5.2.1

SA 8 The system shall employ pre-programmed responses to external stimuli (as specified or TBD) (e.g., a change in location, a change in received signal strength, threat detection, etc.)

7.5.2.1

SA 9 The system shall be able to process commands from the network management system.

7.5.2.1

SA 10 The system shall be able to execute commands from the network management system.

7.5.2.1

SA 11

Cognitive Control

The system shall be capable of consuming digital policy instructions and making its own spectrum access decisions within the constraints of those policies.

7.5.2.2

SA 12

The system's internal decision making logic shall take into account multiple internal factors (e.g., internal state, location, performance limits, configuration, etc.) to make and execute internal decisions.

7.5.2.2

SA 13

The system's internal decision making logic shall take into account multiple external factors (e.g., Received instructions, location change, mission change, EMOE, etc.) to make and execute tailored responses.

7.5.2.2

SA 14 Intelligent

Control

The system shall incorporate sophisticated reasoners capable of improving operating or mission performance based on past performance and trends.

7.5.2.3

SA 15

Functional/State data exchange &

reporting.

The systems shall be able to append data reporting with configuration, integrity, performance, behavior and mission posture information.

7.5.3

SA 16 The system shall be able to relay data from other SDS. 7.5.3

SA 17 The system shall be able to exchange data with other SDS. 7.5.3

SA 18 The system shall be able to consume and produce data in the Standard Spectrum Resource Format (SSRF). (see MCEB PUB 8)

7.5.3


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SA

Network Management 7.6

NM 1

Network Management

The network standards and protocols utilized will be listed in the Standards Profile (StdV-1) of the DoDAF architectural views.

7.6

NM 2 Each node of the system shall incorporate the ability to be remotely commanded by a network management system.

7.6

NM 3 As an option, each node of the system shall be able to operate independently.

7.6

NM 4

Network Overhead Reduction

The system shall employ an effective MAC protocol strategy to minimize packet collisions.

7.6.1.1

NM 5 The system shall employ a transport control strategy that optimizes spectrum and throughput efficiency for wireless networks.

7.6.1.2

NM 6 The system shall employ an efficient network routing strategy that minimizes network control overhead (is the amount of additional information required to maintain network services).

7.6.2.1

NM 7 Topology

management The system shall leverage the directionality of the adaptive antennas to optimize routing schemes and network topology.

7.6.2.2

NM 8 Access Priority The system shall employ a prioritized assignment strategy in order to optimize data handling and throughput.

7.6.3

NM 9 QoS The network's (or system's) frequency assignment strategy shall take into account the available bandwidth to optimize network efficiency and Quality of Service.

7.6.4

NM 10 Link Monitoring The network's (system's) assignment strategy shall employ link quality monitoring to optimize network efficiency and Quality of Service.

7.6.5

NM 11 Spectrum Mgt

Integration The system shall be able to automatically request and receive assignments of spectrum resources.

7.6.6

NM

Data management 7.7

DM 1 Filtering The system shall filter out duplicative or corrupted data before transmitting it.

7.7.1

DM 2 Onboard

Processing

The system shall pre-process (e.g., sort, analyze, correlate, prioritize and/or fuse) any raw data before transmission to reduce data volume.

7.7.2


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DM 3 Data Throttling The system shall dynamically manage data flows and flow rates so that the maximum amount of data can be transported over a given time period and a variable bandwidth or vice versa.

7.7.3

DM 4 Data

Compression The system shall employ a suitable data compression scheme in order to reduce data demand.

7.7.4

DM 5

Encryption

The system shall not use more than one layer of encryption unless absolutely required by established policy.

7.7.5

DM 6 System or Network topology diagrams shall clearly indicate where data encryption is necessary and where 2 or more layers of encryption are being utilized.

7.7.5

DM 7 The Data Encryption type and format utilized will be listed in the Standards Profile (StdV-1) of the DoDAF architectural views.

7.7.5

DM 8 Data Error

Detection & Correction

The system shall employ suitable data error & correction schemes in order to minimize the number of repeat transmissions of data.

7.7.6

DM 9 Date recording The system shall only record filtered and processed data to maximize data storage efficiency.

7.7.7

DM


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Appendix F – Best Practices for Compliance

1) Retain a spectrum SME on your staff or contract with one to help – In addition to attaining an

SSS KPP endorsement, the Certification, SSRA and E3 processes require a high degree of RF

spectrum engineering expertise to navigate and complete. Each of these processes takes

multiple months to complete and a SME will help ensure that your program does not experience

any unnecessary delays in obtaining final certification and success.

2) Contact your Service Spectrum Management Office (SMO) early and establish a relationship

with one of their representatives. The Service SMOs have experienced personnel on staff who

can help you understand and navigate the process.

a. Service SMO offices

i. Army Spectrum Management Office (ASMO) [Mr. Steve Tucker, Chief of

Engineering & Certification: [email protected] or

ii. Navy & Marine Corps Spectrum Center (NMSC) [Contact Mr. Kevin Laughlin.

Chief of Operations and Certification: [email protected] or (301)225-

3692]

iii. Air Force Spectrum Management Office (AFSMO) [Mr. Randy Whittington,

Director of Spectrum Support: [email protected] or (301)225-

3744]

3) Specify EMS compliance documents as CDRLs on your development contract – Compliance with

the spectrum supportability requirements requires significant amounts of data from the

equipment manufacturer. If you do not have a full time spectrum SME on your staff, ensure the

required documents are specific as deliverables on your contracts.

4) Allocate sufficient time, consideration and resources to adequately model, simulate and test

your SDS for EMS effects and performance – As with any complex system, M,S & T will

significantly reduce development risks. Spectrum M, S & T is highly specialized and maximizing

its benefits requires proper resourcing and planning. DO NOT ACCEPT MANUFACTURER’S

PERFORMANCE CLAIMS AT FACE VALUE. Require testing to verify these.

5) Discuss the Spectrum KSAs and requirements with your system’s Operational Sponsor.

Developing systems that incorporate the spectrum KSA attributes may require investments

trade-offs and prioritization. The operational sponsor must be fully engaged in all of these

decisions.

6) Contact the Joint Staff, Strategy, Capabilities and Analysis Branch (J8) and/or the Force

Application Division when developing your JCDIS required Milestone documents. These offices

can provide valuable insights as to how to comply with the EMS Survivability process.

7) Conducting a proper threat analysis for a new system takes time and will evolve with the

maturity of that system. At the beginning of the Material Solution Analysis phase, the

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program office or capability sponsor should establish a close relationship with the

appropriate intelligence production center for their Service and actively participate in the

Threat Steering Group that will be stood up to oversee the development, production and

updating of the STAR. It is critical that the program office take a proactive role in this

working group. Close coordination from the program office will help ensure that the

threat analysis is sufficiently detailed and comprehensive enough to accurately effect

requirements development and design decisions.

8) Develop a written strategy for how the system will defeat or mitigate the most

challenging EMS threats identified in the STAR. In this strategy, spell out all the features

and defense-in-depth components that will be employed to execute this strategy. Then

ensure that all these features and components are specified in the appropriate capability

requirements documents.


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Appendix G – Acronyms

AESA Active Electronically Scanned Array

AFH Adaptive Frequency-Hopping

ALE Automatic Link Establishment

AM Aeronautical Mobile

AoA Analysis of Alternatives

APA Additional Performance Attribute

ARQ Automatic Repeat Request

AS Acquisition Strategy

BC Broadcasting

CDD Capability Development Document

CFAR Constant False Alarm Rate

CM Countermeasures

CPD Capability Production Document

CREW Counter Remote Controlled Improvised Explosive Device (RCIED) Electronic Warfare

CSS Chirp Spread Spectrum

DE Directed Energy

DEA Defensive Electronic Attack

DEW Directed Energy Weapon

DF Direction Finding

DIA Defense Intelligence Agency

DRFM Digital Radio Frequency Memory

DSSS Direct-Sequence Spread Spectrum

E3 Electromagnetic Environmental Effects

EA Electronic Attack

EC Electromagnetic Compatibility

ECC Error Correcting Code

ECCM Electronic Counter-Counter Measures

ELF Extremely Low Frequency

EMC Electromagnetic Compatibility

EME Electromagnetic Environment

EMI Electromagnetic Interference

EMI Electromagnetic Interference

EMOE Electromagnetic Operating Environment

EMP Electromagnetic Pulse

EMS Electromagnetic Spectrum

EMV Electromagnetic Vulnerability

EO Electro-Optical

EP Electronic Protect

ES Electronic Support

ESD Electrostatic Discharge

EW Electronic Warfare

FEC Forward Error Correction

FEC Forward Error Correction


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FHSS Frequency-Hopping Spread Spectrum

FX Fixed

GM Ground Mobile

GPS Global Positioning System

HERF Hazards of Electromagnetic Radiation to Fuel

HERO Hazards of Electromagnetic Radiation to Ordnance

HERP Hazards of Electromagnetic Radiation to Personnel

IC Intelligence Certification

ICD Initial Capabilities Document

IED Improvised Explosive Device

IEEE Institute of Electrical & Electronics Engineers

IR Infrared

IRCM Infra-Red Countermeasures

ISP Information Support Plan

JCIDS Joint Capabilities Integration and Development System

KPP Key Performance Parameter

KSA Key System Attribute

LNA Low Noise Amplifiers

LPD Low Probability of Detection

LPI Low Probability of Interception

LTE Long-Term Evolution

MAC Media Access Control

MAHN Mobile Ad Hoc Network

MANETs Mobile Ad Hoc Networks

MATDEV Material Developer

MDA Milestone Decision Authority

MIMO Multiple In Multiple Out

MM Maritime Mobile

MOVs Metal Oxide Varistors

MS Milestone

MSE Mean Squared Error

MUOS Mobile User Objective System

NIST National Institute of Standards and Technology

NTIA National Telecommunications and Information Administration

OFDM Orthogonal Frequency-Division Multiplexing

ONI Office of Naval Intelligence

OTH Other electronics or electrical components

PF Platforms

PL Passive Listening

PM Program Manager

PPP Program Protection Plan

PRF Pulse Repetition Frequency

P-Static Precipitation Static

QAM Quadrature Amplitude Modulation

QoS Quality of Service

RADAR Radio Detection And Ranging


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RD Radio Determination

RF Radio Frequency

RF Radio Frequency

RO Requirements Officer

SA Satellite

SATCOM Satellite Communication

SCI Sensitive Compartmented Information

SDS Spectrum Dependent System

SDS All other systems

SINR Signal + Interference to Noise Ratios

SIPRNet Secret Internet Protocol Router Network

SONAR Sound Navigation and Ranging

SoS Systems of Systems

SP Spectrum Protection

SPEED System Planning Engineer & Evaluation Device

SSRA Spectrum Supportability Risk Analysis

SSRF Standard Spectrum Resource Format

STAR System Threat Assessment Report

SXXI Spectrum 21

TCP Transport Control Protocol

TEMP Test and Evaluation Master Plan

THSS Time-Hopping Spread Spectrum

TTP Tactics Techniques and Procedures

TVS Transient Voltage Suppressors

UHF Ultra-High Frequency

UV Ultra Violet

UWB Ultra-Wideband

WARM Wartime Reserve Mode

WiFi Wireless Fidelity

RFP Request for Proposal

TSG Threat Steering Group


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Appendix H – Glossary active electronically scanned array (AESA)

An active electronically scanned array (AESA), also known as active phased array radar (APAR), is a type of phased array radar whose transmitter and receiver (transceiver) functions are composed of numerous small solid-state transmit/receive modules (TRMs). AESA radars aim their "beam" by emitting separate radio waves from each module that interfere constructively at certain angles in front of the antenna. Advanced AESA radars can improve on the older passive electronically scanned array (PESA) radars by spreading their signal emissions out across a band of frequencies, which makes it very difficult to detect over background noise, allowing ships and aircraft to broadcast powerful radar signals while still remaining stealthy.

adaptive frequency hopping

A more advance spread-spectrum technique is Adaptive Frequency-hopping spread spectrum (AFH) (as used in Bluetooth) which improves resistance to EMI by avoiding crowded frequencies in the hopping sequence.

automatic link establishment (ALE)

High frequency (HF) radio systems employing modern automatic link establishment (ALE) protocol can operate much more reliably using lower power and less expensive antennas than conventional manually operated systems. The ALE systems utilize link quality assessment to find the best frequency for current operations from a scan list of candidate frequencies.

aeronautical mobile A mobile service between aeronautical stations and aircraft stations, or between aircraft stations, in which survival craft stations may participate; emergency position-indicating radio beacon stations may also participate in this service on designated distress and emergency frequencies.

automatic repeat request (ARR)

An error-control method for data transmission that uses acknowledgements (messages sent by the receiver indicating that it has correctly received a data frame or packet) and timeouts (specified periods of time allowed to elapse before an acknowledgment is to be received) to achieve reliable data transmission over an unreliable service. If the sender does not receive an acknowledgment before the timeout, it usually re-transmits the frame/packet until the sender receives an acknowledgment or exceeds a predefined number of re-transmissions.

constant false alarm rate (CFAR)

A common form of adaptive algorithm used in radar systems to detect target returns against a background of noise, clutter and interference

chirp spread spectrum (CSS)

A spread spectrum technique that uses wideband linear frequency modulated chirp pulses to encode information. A chirp is a sinusoidal signal whose frequency increases or decreases over time (often with a polynomial expression for the relationship between time and frequency). Used to mitigate the negative effects of channel noise in some cases to reduce signal detectability.

directed energy (DE)

Highly focused energy (sound, light, microwaves, etc.).

defensive electronic attack (DEA)

Sometimes referred to as self-protection jamming or Electronic Countermeasures, such measures are designed to disrupt or foil an adversary’s ability to detect, track, target or attack using the EMS.

directed energy weapon (DEW)

A weapon designed to emit highly focused energy (sound, light, microwaves, etc.) at a target to degrade damage or destroy it.

direction finding (DF)

Also called radio direction finding (RDF), this is the measurement of the direction from which a received signal was transmitted. If multiple sensors are utilized with

https://en.wikipedia.org/wiki/Radar

https://en.wikipedia.org/wiki/Receiver_(radio)

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suitable separation, the lines of bearing to the signal can be triangulated to determine a location of the source. A single sensor can also use multiple lines of bearing produced over time or by employing more sophisticated techniques like signal phase or Doppler comparison.

digital radio frequency memory (DRFM)

A spoofing technique that has become more common for radar spoofing is the use of Digital Radio Frequency Memory (DRFM) which digitally captures and retransmits a radar signal. Being a coherent representation of the original signal, the transmitting radar will not be able to distinguish it from other legitimate signals it receives and processes as targets.

direct-sequence spread spectrum (DSSS)

A spread spectrum modulation technique. Spread spectrum systems are such that they transmit the message bearing signals using a bandwidth that is in excess of the bandwidth that is actually needed by the message signal. This spreading of the transmitted signal over a large bandwidth makes the resulting wideband signal appear as a noise signal which allows greater resistance to intentional and unintentional interference with the transmitted signal.

electromagnetic environmental effects (E3)

Electromagnetic environmental effects or E3 encompasses the electromagnetic effects addressed by the disciplines of EMC, EMI, EM vulnerability, EM pulse, electronic protection, electrostatic discharge, and EMR hazards to personnel, ordnance, and fuels or volatile materials. E3 includes the effects generated by all EME contributors including RF systems, ultra-wideband devices, high-power microwave systems, lightning, and precipitation static.

electronic attack (EA)

A division of electronic warfare involving the use of electromagnetic energy, directed energy, or antiradiation weapons to attack personnel, facilities, or equipment with the intent of degrading, neutralizing, or destroying enemy combat capability. It is considered a form of fires.

EMS Reliant System Nearly identical to SDS below but with a broader applicability that includes systems that depend upon IR, Visible and UV light waves.

error correcting code (ECC)

Error correcting code (ECC) checks read or transmitted data for errors and corrects them as soon as they are found. ECC is similar to parity checking except that it corrects errors immediately upon detection.

electronic counter-countermeasures (ECCM)

Part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as electronic protective measures (EPM), chiefly in Europe. In practice, EPM often means resistance to jamming.

extremely low frequency (ELF)

Electromagnetic radiation (radio waves) with frequencies from 3-30 Hz

electromagnetic compatibility (EMC)

The ability of systems, equipment, and devices that use the electromagnetic spectrum to operate in their intended environments without causing or suffering unacceptable or unintentional degradation because of electromagnetic radiation or response.

electromagnetic environment (EME)

The resulting product of the power and time distribution, in various frequency ranges, of the radiated or conducted electromagnetic emission levels encountered by a military force, system, or platform when performing its assigned mission in its intended operational environment.

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electromagnetic interference (EMI)

Any electromagnetic disturbance, induced intentionally or unintentionally, that interrupts, obstructs, or otherwise degrades or limits the effective performance of electronics and electrical equipment.

electromagnetic operational environment (EMOE)

The background electromagnetic environment produced by all friendly, neutral, and adversarial electromagnetic emissions within the electromagnetic area of influence associated with a given operational area.

electromagnetic pulse (EMP)

The electromagnetic radiation from a strong electronic pulse, most commonly caused by a nuclear explosion that may couple with electrical or electronic systems to produce damaging current and voltage surges.

electromagnetic spectrum (EMS)

The range of frequencies of electromagnetic radiation from zero to infinity. It is divided into 26 alphabetically designated bands.

electromagnetic vulnerability (EMV)

The characteristics of a system that cause it to suffer a definite degradation (incapability to perform the designated mission) as a result of having been subjected to a certain level of electromagnetic environmental effects.

electro-optical (EO) Components, devices (e.g. Lasers, LEDs, waveguides etc.) and systems which operate by the propagation and interaction of light with various tailored materials. Usually associated with sensors that detect visible light.

electronic protection (EP)

A division of electronic warfare involving actions taken to protect personnel, facilities, and equipment from any effects of friendly or enemy use of the electromagnetic spectrum that degrade, neutralize, or destroy friendly combat capability.

electronic support (ES)

Electronic Support (ES) or Electronic Support Measures (ESM) is the division of electronic warfare involving actions taken under direct control of an operational commander to detect, intercept, identify, locate, record, and/or analyze sources of radiated electromagnetic energy for the purposes of immediate threat recognition (such as warning that fire control RADAR has locked on a combat vehicle, ship, or aircraft) or longer-term operational planning and intelligence.

electrostatic discharge (ED)

The sudden flow of electricity between two electrically charged objects caused by contact, an electrical short or dielectric breakdown. A buildup of static electricity can be caused by turbocharging or by electrostatic induction.

electronic warfare (EW)

Military action involving the use of electromagnetic and directed energy to control the electromagnetic spectrum or to attack the enemy. Also called EW.

forward error correction (FEC)

In telecommunication, information theory, and coding theory, forward error correction (FEC) or channel coding is a technique used for controlling errors in data transmission over unreliable or noisy communication channels.

frequency-hopping spread spectrum (FHSS)

Is one of two basic modulation techniques used in spread spectrum signal transmission. It is the repeated switching of frequencies during radio transmission, often to minimize the effectiveness of detection or interception.

global positioning system (GPS)

A satellite-based radio navigation system operated by the Department of Defense to provide all military, civil, and commercial users with precise positioning, navigation, and timing.

hazards of electromagnetic radiation to fuels (HERF)

The potential hazard that is created when volatile combustibles, such as fuel, are exposed to electromagnetic fields of sufficient energy to cause ignition.


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hazards of electromagnetic radiation to ordnance (HERO)

The danger of accidental actuation of electro-explosive devices or otherwise electrically activating ordnance because of radio frequency electromagnetic fields.

hazards of electromagnetic radiation to personnel (HERP)

The potential hazard that exists when personnel are exposed to an electromagnetic field of sufficient intensity to heat the human body.

improvised explosive device (IED)

A device placed or fabricated in an improvised manner incorporating destuctive, lethal, noxious, pyrotechnic, or incendiary chemicals and designed to destroy, incapacitate, harass, or distract. It may incorporate military stores, but is normally devised from nonmilitary components.

Infrared (IR) Invisible radiant energy, electromagnetic radiation with longer wavelengths than those of visible light, extending from the nominal edge of the red visible spectrum at 700 nanometers (frequency 430 THz) to 1 mm (300 GHz) (although people can see infrared up to at least 1050 nm in experiments). Most of the thermal radiation emitted by objects near room temperature is infrared.

infrared countermeasure (IRCM)

Measures designed to conceal or deceive the infrared sensors used by an adversary to detect, track, characterize or target a system.

Light amplification by stimulated emission of radiation (LASER)

A device that generates an intense beam of coherent monochromatic light (or other electromagnetic radiation) by stimulated emission of photons from excited atoms or molecules.

low noise amplifiers (LNA)

An electronic amplifier that amplifies a very low-power signal without significantly degrading its signal-to-noise ratio. An amplifier will increase the power of both the signal and the noise present at its input. Low-noise amplifiers are designed to minimize the additional noise. Designers minimize the additional noise by considering tradeoffs that include impedance matching, choosing the amplifier technology, and selecting low-noise biasing conditions.

mobile ad-hoc network (MANET)

A continuously self-configuring, infrastructure-less network of mobile devices connected without wires. MANETs usually employ a routable networking environment on top of a Link Layer ad-hoc network.

multiple in multiple out (MIMO)

In radio, multiple-input and multiple-output, or MIMO (pronounced as "my-moh" or "me-moh"), is a method for multiplying the capacity of a radio link using multiple transmit and receive antennas to exploit multipath propagation. MIMO has become an essential element of wireless communication standards including IEEE 802.11n (Wi-Fi), IEEE 802.11ac (Wi-Fi), HSPA+ (3G), WiMAX (4G), and Long Term Evolution (4G).

metal oxide varistors (MOV)

The most common type of varistor. A varistor is an electronic component with an electrical resistance that varies with the applied voltage. Also known as a voltage-dependent resistor (VDR), it has a nonlinear, non-ohmic current–voltage characteristic that is similar to that of a diode. In contrast to a diode however, it has the same characteristic for both directions of traversing current. Varistors are used as control or compensation elements in circuits either to provide optimal operating conditions or to protect against excessive transient voltages.


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When used as protection devices, they shunt the current created by the excessive voltage away from sensitive components when triggered.

mean squared error A measure of how close a fitted line is to data points. For every data point, you take the distance vertically from the point to the corresponding y value on the curve fit (the error), and square the value.

mobile user objective system (MUOS)

A narrowband military communications satellite system that supports a worldwide, multi-Service population of users in the ultra-high frequency band. The system provides increased communications capabilities to newer, smaller terminals while still supporting interoperability with legacy terminals. MUOS is designed to support users that require greater mobility, higher bit rates and improved operational availability.

national institute of standards and technology (NIST)

The federal technology agency that works with industry to develop and apply technology, measurements, and standards.

national telecommunications and information administration (NTIA)

An agency of the United States Department of Commerce that serves as the President's principal adviser on telecommunications policies pertaining to the United States' economic and technological advancement and to regulation of the telecommunications industry.

Orthogonal Frequency-Division Multiplexing(OFDM)

A method of encoding digital data on multiple carrier frequencies.

pulse repetition frequency (PRF)

The number of pulses of a repeating signal in a specific time unit normally measured in pulses per second. The term is used within a number of technical disciplines, notably RADAR.

precipitation static (P-Static)

Static produced in airborne radio equipment by the striking of rain, snow, hail, dust particles or other particles in the atmosphere on the antenna and surfaces of an airplane.

quadrature amplitude modulation (QdAM)

A form of modulation which is widely used for modulating data signals onto a carrier used for radio communications.

radio detection and ranging (RADAR)

Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain.

radio determination The determination of the position, velocity or other characteristics of an object, or the obtaining of information relating to these parameters, by means of the propagation properties of radio waves.

radio frequency (RF) Any of the electromagnetic wave frequencies that lie in the range extending from around 3 kHz to 275 GHz, which include those frequencies used for communications or radar signals

signal + interference to noise ratios (SNIR)

In information theory and telecommunication engineering, the signal-to-interference-plus-noise ratio (also known as the signal-to-noise-plus-interference ratio - SNIR) is a quantity used to give theoretical upper bounds on channel capacity (or the rate of information transfer) in wireless communication systems such as networks.

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Spectrum Dependent System (SDS)

All electronic systems, subsystems, devices, and/or equipment that depend on the use of the spectrum to properly accomplish their function(s) without regard to how they were acquired (full acquisition, rapid acquisition, Joint Concept Technology Demonstration, etc.) or procured (commercial off-the-shelf, government off-the-shelf, non-developmental items, etc.). Sometimes written as S-D Systems. (MIL-STD-464)

spectrum protection (SP)

Spectrum Protection (SP) is a hybrid term that combines those aspects of Electronic Protection, Electronic Support and Electronic Attack that contribute to system survivability from EMS threats.

spectrum XXI Spectrum XXI is a client/server, Windows-based software system that provides frequency managers with a single information system to address spectrum management automation requirements.

transport control protocol (TCP)

A core protocol of the Internet protocol suite. It originated in the initial network implementation in which it complemented the Internet Protocol (IP). Therefore, the entire suite is commonly referred to as TCP/IP. TCP provides reliable, ordered, and error-checked delivery of a stream of octets between applications running on hosts communicating over an IP network. TCP is the protocol that major Internet applications such as the World Wide Web, email, remote administration and file transfer rely on. Applications that do not require reliable data stream service may use the User Datagram Protocol (UDP), which provides a connectionless datagram service that emphasizes reduced latency over reliability.

time-hopping spread spectrum

A time hopping system is a spread spectrum system in which the period and duty cycle of a pulsed RF carrier are varied in a pseudorandom manner under the control of a coded sequence. The transmission hops in time

transient voltage suppressor (TVS)

A general classification of an array of devices that are designed to react to sudden or momentary overvoltage conditions.

ultra-high frequency (UHF)

Is the ITU designation for radio frequencies in the range between 300 MHz and 3 GHz. Also known as the decimeter band as the wavelengths range from one meter to one decimeter.

ultra violet (UV) Ultraviolet light is a form of radiation which is not visible to the human eye. It's in an invisible part of the "electromagnetic spectrum". Radiated energy, or radiation, is given off by many objects: a light bulb, a crackling fire, and stars are some examples of objects which emit radiation.

ultra-wideband (UWB)

Ultra-wideband (also ultra-wide band and ultraband) is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum.

wartime reserve mode (WARM)

Wartime reserve modes are military procedures held in reserve for wartime or emergency use. They concern the characteristics and operating procedures of sensor, communications, navigation aids, threat recognition, weapons, and countermeasures systems. Since the military effectiveness of these procedures links to them being unknown to or misunderstood by opposing commanders before they are used, stopping their use by making them reserved has the effect of ensuring they remain effective by making it impossible for them to be known about in advance by such opposing commanders. This prevents them being exploited or neutralized.

Wi-Fi Wi-Fi is any "wireless local area network" (WLAN) product based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11x standard. A common

https://en.wikipedia.org/wiki/Communications_protocol

https://en.wikipedia.org/wiki/Internet_protocol_suite

https://en.wikipedia.org/wiki/Internet_Protocol

https://en.wikipedia.org/wiki/Reliability_(computer_networking)

https://en.wikipedia.org/wiki/Error_detection_and_correction

https://en.wikipedia.org/wiki/Octet_(computing)

https://en.wikipedia.org/wiki/World_Wide_Web

https://en.wikipedia.org/wiki/Email

https://en.wikipedia.org/wiki/Remote_administration

https://en.wikipedia.org/wiki/Remote_administration

https://en.wikipedia.org/wiki/File_transfer

https://en.wikipedia.org/wiki/User_Datagram_Protocol

https://en.wikipedia.org/wiki/Connectionless_communication

https://en.wikipedia.org/wiki/Datagram

https://en.wikipedia.org/wiki/Latency_(engineering)

https://en.wikipedia.org/wiki/Military

https://en.wikipedia.org/wiki/War

https://en.wikipedia.org/wiki/Military_communications

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misconception is that the term Wi-Fi is short for "wireless fidelity," however this is not the case. Wi-Fi is simply a trademarked phrase used for any system that uses the IEEE 802.11x wireless standards.

Documents

EMS Survivability Guidebook - DAU Sponsored...EMS Survivability Guidebook 7 1. Purpose The purpose of this guidebook is to assist Requirements Officers (ROs) material developers (MATDEVs)