CRI: Wireless Internet Building Blocks for Research, Policy, and EducationDirk Grunwald, Timothy X Brown, Tom Lookabaugh, Olgica Milenkovic, Douglas Sicker

University of Colorado, Boulder 80309-0530

Wireless communication depends on using a shared resource, the radio spectrum. The spectrum is man-aged by government regulators to avoid interference among different services and users, but that spectrum isinefficiently used. For instance, there are existing incumbents across the spectrum, but, radio surveys showthat only 10% of spectrum is actually used. Traditional spectrum management is now poised to exploitadvances in communication, networking, and computing technology that enables dramatic increases in theuse of the spectrum.

There are many technical challenges in such agile spectrum use, and their solution encompasses manyaspects of computer science and engineering. Realistic solutions to these problems require an integratedapproach. For example, agile spectrum use may require the ability to exploit non-contiguous bands inthe spectrum. Understanding how to use such a collection of bands poses challenges for coding theory,media access protocols and middleware layers that negotiate the use of such spectrum. Determining whichbands are available poses similar challenges, and the development of a measurement infrastructure andmethodology is an integral part of the proposal.

The equipment requested in this proposal will enable research into the question of how could spectrumbe managed to increase its utilization and in what ways can we transition to these more efficient regimes.The proposed equipment will support measurements of broad ranges of spectrum, allowing researchers todevelop models of spectrum utilization and as diagnostic tools for experiments. The equipment will alsosupport a flexible wireless testbed across several sections of spectrum, building upon an existing infras-tructure for wireless data networking. Lastly, the equipment will provide an infrastructure that will allowthe real-time capture and analysis of the wireless monitoring system as well as computational facilities forprotocol, coding and middleware evaluation.

This proposal combines researchers in areas of networking, wireless networking, coding theory, middle-ware, as well as experts in legal and policy issues. The researchers will combine the resources of the Depart-ment of Computer Science with the Department of Electrical and Computer Engineering and the resourcesof Interdisciplinary Telecommunications Research Center (ITRC) to expand research abilities in technologyfor agile spectrum management, coding for wireless communications and systems and assessment of cur-rent spectrum use. The interdisciplinary focus of this work presents unique challenges for graduate studentsworking in this area.

Intellectual merits: The proposed research will allow experimentation in many different aspects of pro-grammable wireless networks, including the use of multi-band protocols for robust communication, man-agement structures for dynamic spectrum allocation, and experimentation with novel network devices, suchas phase array antennas, multi-input/multi-output and ultra-wide band systems. The project will also de-velop novel media access The efforts will also drive development of research oriented features for suchinfrastructure, such as monitoring, visualization, and control.

Broader Impacts: Programmable wireless networks are poised to greatly influence spectrum allocationpolicies. In order to make sound policy decisions, technology demonstrations and investigations are needed.Moreover, there must be greater understanding of the unique characteristics of this communication mediumin educational programs. In keeping with prior NSF Research Initiation awards at Colorado, this challengewill be addressed through an interdisciplinary curriculum developed under the proposal.

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CRI: Wireless Internet Building Blocks for Research, Policy, and Education

Contents

I EXECUTIVE SUMMARY 1

II RESULTS FROM PRIOR NSF SUPPORT 2

A Results From Prior NSF Infrastructure Awards 3

B Other Relevant Work By Principals 4

III RESEARCH INFRASTRUCTURE DESCRIPTION 5

C Wireless Measurement and Collection Equipment 6

D Radio Building Block Components 7

IV PROJECT DESCRIPTION 7

E Research Problem 8

F Research To Be Undertaken With Proposed Equipment 8

F.1 Measurements of Wireless Spectrum: Key To Strong Research . . . . . . . . . . . . . . . . 8

F.2 Middleware for Spectral Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

F.3 Information Theoretic Interactions With Wireless Communications . . . . . . . . . . . . . . 11

F.4 Networking Challanges in Wireless Networks . . . . . . . . . . . . . . . . . . . . . . . . . 13

G Educational Initiatives with the Proposed Equipment 15

H Participant Synergy 15

I Leveraging the Infrastructure 16

J Impact of Proposal 16

V COORDINATION PLAN 17

VI Bibliography 19

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VII BUDGET JUSTIFICATION 24J.1 Matching Funds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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Part I

EXECUTIVE SUMMARY

We propose to broaden research capabilities inagile spectrum management. Wireless communication spec-

trum is a valuable, and limited, commodity. Spectrum is valuable because of the increasing use of and

dependence on wireless communications devices. Existing systems, such as cellular or radio communi-

cations use a limited amount of the current spectrum, but are essential to safety and productivity. Other

portions of the spectrum are currently allocated to emergency response, television, nautical and aerospace

applications, and each of these applications are critical to the national infrastructure. New applications are

constantly emerging - for example, researchers in sensor networks envision thousands or millions of wireless

transcievers communicating.

However, spectrum is also limited. In particular,

Figure 1: Current Spectrum Allocation Is Static

certain portions of the RF spectrum are more valuable

than others – for example, the lower frequencies tend to

propogate further, but there is inheriently limited band-

width available in those frequencies. Current spectrum

allocation policies rely onstatic allocations. Figure 1

shows spectrum allocation in the United States. Spec-

trum allocations between 30Mhz and 3Ghz include a

number of commercial applications as well unlicensed

bands. Small amounts of spectrum are indicated for

Industrial Scientific, and Medical (ISM) applications.

Often, this is spectrum that would have limited com-

mercial application – for example, the 2.4Ghz ISM spectrum used by WiFi wireless network occupies the

spectrum generated by microwave ovens. There is a current debate to the degree to which current spectrum

allocations are used. For example, in some sparsely populated locales, little, if any, of the spectrum alloca-

tion for television stations is actually used. Likewise, some spectrum is reserved to eliminate interference,

but is used infrequently. Lastly, some spectrum is reserved to eliminatepotentialinterference, but that inter-

ference may not arise because mitigating factors such as attenuation due to buildings, transmit power levels

and directionality may make interference unlikely.

Vision and Research Focus

Flexible and robust management of this spectrum poses a number of significant research challanges across

a number of disciplines. This proposal will focus on four technical challanges:

1. Understanding Current Spectrum Usage

2. Middleware To Support Agile Spectrum Use

3. Advanced Coding For Wireless Networks

4. Networking For Agile Spectrum Use

One of the first questions is understanding how spectrum is actually used; while this would appear to

be a simple question, it is actually complex. Four of the investigators involved in this proposal have been

awarded an NSF ITR grant “ITR-ECS-soc: Spectrum Management Towards Spectrum Plenty” that focuses

explicitly on the issue of assessing what spectrum is being used as well as technologies for determining and

communicating this information.

Once spectrum measurements have determined local spectrum usage, there is a need to coordinate spec-

trum use across broader areas. This is necessary because spectrum measurement equipment may not share

the same characteristics as users of that spectrum – for example, measurement systems may have limited

receiver sensitivity, while a transmitter may use a high gain antenna, or higher transmit power, or may use

a low-probability to detect wideband technique. Thus, we will be developingmiddlewaresystems that help

coordinate the use, sharing, and allocation of spectrum.

Our conjecture is that usable spectrum will often be fragmented; although static spectrum allocation

results in contigious sections of spectrum devoted to specific applications, this may not be possible or desir-

able in general, provided the existing radio technology is able to accomodate multiple bands simultaniously.

Contigious bandwidth increases the complexity of bandwidth allocating, analgous to the problem of internal

fragmentation in memory allocation systems. There are benefits to multi-band communication – different

bands are sensitive to different noise sources and have different multipath and and interference characteris-

tics. This presents challanges in coding designs since the characteristics of forward error correction codes

for such systems will be fundementally different than current FEC’s.

Multiband communication also increases the complexity of network protocol designs, introducing the

need for novel MAC protocols and the need for new routing and QoS protocols. Likewise, the introduction of

steerable antennas increases the complexity of adaptive routing algorithms and bandwidth allocation. Work

in this area is on-going, and the proposed equipment would move the current work from simulation-based

studies to experimental deployments.

Part II

RESULTS FROM PRIOR NSF SUPPORT

The University of Colorado is the flagship public research university in the state of Colorado. It was founded

in 1876, the year that Colorado became a state. It currently consists of approximately 26,000 students, of

whom 20,500 are undergraduates and 5,500 are graduate students. The University is located in Boulder,

Colorado.

The Department of Electrical and Computer Engineering was founded in 1890 in the earliest days of the

College of Engineering. The department currently has about 40 faculty, with research strengths including

communications, computer engineering, controls, electromagnetics, optics, power electronics, and remote

sensing. The department is part of an NSF IGERT and was home to an NSF ERC.

The Department of Computer Science was founded in 1970, and its Ph.D. program was established in

1971. The department currently has about 23 faculty, with research strengths including computer systems

(database, operating systems, architecture), software engineering, parallel and numerical computation, and

cognitive science.

The Department of Computer Science has been the recipient of four consecutive five-year NSF infras-

tructure grants: a Coordinated Experimental Research grant beginning in 1985, an Institutional Infrastruc-

ture grant beginning in 1990, a Research Infrastructure grant in 1995 and the current Research Instructure

grant beginning in 2000. These awards have accomplished the goal of the original NSF CISE/CER program

– they have dramatically improved the ability of our department to conductexperimentalcomputer science,

and have led to a continued growth in the size and reputation of our department.

This proposal expands on that past success by including faculty in both Computer Science and Electrical

and Computer Engineering.

A Results From Prior NSF Infrastructure Awards

The University of Colorado’s current Research In-

Figure 2: Mantis Sensor Node Developed Un-

der Current Ri. For more information, see

http://mantis.cs.colorado.edu

frastructure project provides infrastructure for the “Dig-

ital CommonSpace,” an infrastructure for ubuiqutious

computing. This project had four components: Small

Commmunication Computer Development; Devices, Sys-

tems and Networks; Dynamic Interconnection Facili-

ties; and, General Applications. Each generation of

CISE infrastructure funding has produced profound changes

in the structure and capabilities of the Computer Sci-

ence Department, and few more than the current RI

grant. Prior infrastructure funding equipped the depart-

ment to use cutting edge supercomputers and worksta-

tions clusters; the current funding has enabled the de-

partment to develop hardware and system prototypes. For example, by being able to support the research

expenses of junior faculty, the department was able to hire faculty interested insensor networksand partially

funded the local development of a sensor network hardware platform. The Mantis sensor node, shown in

Figure 2, provides an extensible platform for work in sensor network deployments and algorithm design.

Other resources provided by the RI grant facilitated experimentation with network processor develop-

ment systems and Xilinx prototyping systems for networking computing. For example, Figure 3 shows a

Xilinx ML300 development system donated by Xilinx for work on using hybrid FPGA’s for high perfor-

mance network processors; the RI grant provided support for CAD tools, test networks and measurement

equipment for that project.

The prior RI grant also provided signficant equipment for experimenting in wireless networking; the

work discussed in the current proposal is a direct out-come of work initiated during the prior research

infrastructure grant. The Department has developed network simulators, multiple wireless networks,ad hoc

routing infrastructures including embedded systems and platforms for deploying and evaluating advanced

wireless network devices such as the prototype phase array antenna mentioned later in this proposal.

One of the most fundemental changes induced by

Figure 3: Xilinx ML300 Development System

For Hybrid FPGA’s

the current RI grant is the structure of the Department’s

research network. Previously, the department had a

fixed network architecture – most equipment was placed

behind a centrally managed firewall, and test or exper-

imental equipment was deployed in a limited number

of locations. This caused significant problems for work

in experimental computer systems, because equipment

had to be physically moved when faster or more flex-

ible network access was needed. During 2003-2004,

Dr. Grunwald led a group to redefine the network needs

for the Department and augmented the existing network

with a flexible “confederated network architecture” that

uses virtual LAN’s and a two tier network architecture to provide a flexible, high performance interconnect

with minimal centralized management. This network design has allowed researchers to bring gigabit net-

working to the desktop, simplified the time to deploy experiments and enabled experiments that would have

been difficult or impossible with the prior network organization. New networks can be configured using

simple utilities and individual groups are responsible for routing, firewall policies and network services.

This organization has also greatly increased the independence of graduate students and faculty when recon-

figuring or adding networks.

Lastly, the prior award provided a moderate amount of computing support for simulations, web services,

data repositories and the like. Moreover, numerous smaller components, such as hand-held PDA’s, tablet

PC’s, location detection and measurement systems were integrated into a number of classes and research

projects, including projects focused on assistive technology for people with cognative disabilities.

The combination of these services has touched all faculty in the Computer Science department, and

enabled numerous new research directions.

B Other Relevant Work By Principals

Tim Brown received the NSF CAREER Award NCR-9624791 “Adaptive Admission Control for Broad-

band Networks,” and NSF Grant NCR-9725778 “High-Performance, Low-Power Wireless Communication”

which funded two doctoral, three masters, and four undergraduate students. The outcomes include methods

for guaranteeing quality of service (QoS) in packet networks while assuming little about the underlying

traffic and network model (e.g. [2, 3, 4, 5, 6, 7, 9, 11, 37, 38]). He has also been supported by the Colorado

Council on Higher Education, Ericsson, Agilent, Siemens, and the Air Force.

Tim Brown, Dirk Grunwald, Dennis Akos and Doug Sicker are jointly working on a newly funded

award,“ITR-ECS-soc: Spectrum Management Towards Spectrum Plenty,” which looks at the intersection of

technology and policy issues in spectrum management.

Dirk Grunwald andTim Brown are jointly working on ANI-0082998 “ITR: Energy and Quality of Service

Aware Ad-Hoc Networking,” We have developed mechanisms to reduce system power inad-hocnetworks,

deployment and simulation platforms; part of this work is described in Section X. Recent work has investi-

gated localization and has generated two masters thesis [27, 40]. The proposal is currently supporting two

masters and three Ph.D. students. Publications from this grant include [1, 8, 10, 15, 24, 33, 34, 35].

Dirk Grunwald: Dirk Grunwald received a NSF Research Initiation Award CCR 9010624 “Empirical

Studies of Process Distribution and Redistribution in Multicomputers,” was an investigator on NSF Grand

Challenge ASC-9217394 “Coupled-Field and GAFD Turbulence,” and was a PI on MIP-9706286 “Memory

Prefetching.” He has also been supported by ARPA, NASA, Hewlett-Packard, Digital Equipment Corpora-

tion, Compaq, Microsoft and the state of Colorado.

Students supported by NSF 0072870 “Speculation Control for Energy Efficiency” have published papers

related to aspects of speculation control and microarchitectural denial of service [12, 14, 20, 26], Additional

funding and equipment for work onthread level speculation controlwas provided by Intel.

NSF Award 9988548 “Energy Efficient Operating Systems for Pocket Computers” has produced papers

on the evaluation of different clock scaling, power efficient disk systems, and energy efficiency in pervasive

computing systems[13, 17, 18, 19]. The project has developed a multi-architecture system for supporting

“clock and voltage scaling” on different computer platforms. Work is progressing beyond the original fo-

cus on clock and voltage scaling to reducing power due to I/O and on other aspects of mobile computing

platforms including privacy and anonymity in mobile systems [22, 23, 21].

NSF Award 0082998 “Energy and Quality of Service Aware Ad-Hoc Networking” with Dr. Tim Brown

has produced and deployed aad hocmobile computing environment that combines elements of the Click

Modular Router, locally developedad hocnetworking components and embedded Linux systems. This

system also uses a co-simulation environment based on extensions to the “ns2” network simulator that lets

the same code base be used in simulation and deployment [34]. This system facilitates investigation into

MAC, network and transport layer improvements for wireless networks [25].

Dr. Grunwald is also a co-PI on an NSF RI award, 0080146 “CISE Research Infrastructure: Digi-

tal Common Space.” This award provided the network and system infrastructure that enabled research in

wireless networks and sensor networking at the University of Colorado.

Dr. Grunwald is a co-PI on an NSF Network Resouces Testbed award, “Heterogeneous Wireless Access

Network Test Bed”, a joint award with Stevens Institute. To date, that proposal has funded work on a com-

mon software router platform coupled with a software defined radio system, developed quality of service

mechanisms for standard 802.11 networks [16] and done some preliminary work on using directional an-

tennas in data networks [32]. This project has also support two undergraduate students who have developed

embedded systems to supportad hocnetworks and evaluated an experimental phase array antenna system.

Figure 4: Comblock Modular R/F Components

Part III

RESEARCH INFRASTRUCTURE DESCRIPTION

The infrastructure acquired under this proposal will be comprised of wireless measurement and collection

equipment; and radio building block components. This part of the proposal provides an overview of the

types of equipment that will be purchased. The research and educational initiatives that this supports will be

discussed later.

C Wireless Measurement and Collection Equipment

This infrastucture will provide fundamental wireless measurement and data analysis capbabilities to the

University of Colorado. We seek equipment that will allow the collection of frequency, time, and logical

measurements and the ability to archive and analyse this data.

Spectrum analyzers covering the spectrum up to 13GHz combined with low-noise amplifiers and highly

selective frontend filters will enable careful measurements of spectrum usage and signals present over the

most significant spectrum. More detailed sudies of specific applications, such as GPS or WiFi, will use com-

mercial receiver elements. Collection of time-domain waveforms will use A/D converters tuned to bands of

interest. We expect a large volume of data to be collected at high rates, particularly with the introduction

of low-cost measurement components. One example of a data collection infrastructure we are planning on

acquiring is theComBlocks system fromhttp://www.comblock.com ). These are modular systems

that can be used to construct measurement and analysis systems such as the one depicted in Figure 4. These

systems combine a variety of low-cost RF front-ends, data processing components and uplink communica-

tion tools. These systems can be produce a tremendous amount of data. For instance a 12bit 50Msps A/D

converter will produce 600Mbps of data, or about 80-100 Mbyte/s. Other data measurements may be at a

lower rate but the studies may take place over longer periods.

The availability of low-cost receivers will enable large monitoring arrays that collectively can produce

high volumes of data. Based on our experience in establishing a gigabit research network, we are planning

to build a special-purpose gigabit network coupled with a small array of data collection systems. Each data

collection system will have a large (≈2TB) high-speed disk array and multiple gigabit ethernet connections.

Although the current ComBlocks only support 100 Mb/s networking, we plan on developing a custom

ComBlock using a Xilinx VIrtex-II/Pro FPGA and fiber connections for remote monitoring; these systems

will be able to download data at gigabit speeds. Unlike our existing research network, this network is

designed purely as a private data collection vehicle, and will be largely fabricated using Dell 6024F gigabit

routers and fiber-optic cabling.

Once collected analyzing this data will require sufficient computing power to filter and manipulate; we

have budgeted a 32-node computing cluster for this purpose. This cluster will have a dedicated interface to

the data storage clusters.

D Radio Building Block Components

We seek interchangeable radio components that will allow the easy mix and matching of components to en-

able a wide variety of radios to quickly be constructed and modified. A basic radio consists of antenna, am-

plifier, frequency up/down converter, modulator/demodulator, and baseband processor. These components

are available in a number of building block forms. First, there are commercially available building blocks

covering each of these components, such as the wide array of components fromhttp://www.comblock.com .

Second, there are radios that have aspects of the different components under software control. Third, the

radio can digitize the signal at any point in this process and allow the components to be realized in software.

Each of these approaches has its merits. Most research and education will focus on only one aspect

of the radio communication at any time and the different approaches allow the user to focus on the aspect

of interest. For example, commercial components emables a student to modify a specific radio component

while providing the remaining components to complete the system. A sofware controlled radio allows a

resercher to study the role of adaptation in communication. Software realizations allow a student to quickly

study the effect of different signal processing and protocol algorithms on radio performance. For this reason,

we will seek a broad approach that acquires equipment of each type.

Part IV

PROJECT DESCRIPTION

E Research Problem

F Research To Be Undertaken With Proposed Equipment

F.1 Measurements of Wireless Spectrum: Key To Strong Research

Spectrum measurements can be taken at several levels and for several purposes. Measurements can be made

at the physical level independent of protocol, or, they can be protocol specific. They can be made for the

purpose of characterizing or for the purpose of exploiting the spectrum.

Physical Spectrum Characterizion It has been well documented that current spectral allocations are un-

derutilized [FCC02a]. However, it is a daunting task to identify and characterize which specific frequency

allocations should be candidates for revision with uniform consensus. As an attempt to address the issue, yet

make the problem tractable, a measurement campaign will be conducted on two diverse frequency bands.

The two bands represent spectral allocations at opposite extremes of the range of those bands that are viewed

as least hospital to unlicensed uses and those viewed as most hospital. The goal of this inquiry will be to

utilize diverse and numerous spectral measurements in a variety of geographic location of these specific

frequency bands to better understand their operating environment, provide insight as to their spectral uti-

lization, and potential for future sharing. Since these two bands represent diverse categories of spectrum

allocation, results of this investigation will allow conclusions to be drawn which bound possible future

spectral adaptations.

The specific bands are: (1) the 2.4 GHz Industrial, Scientific, and Medical (ISM) band [2441.75 41.75

MHz]; and (2) the Global Positioning System (GPS) L1 band [1575.42 10 MHz]. These two bands have

been selected as a result of their diverse characteristics and recent visibility within the proposed spectral

modernization.

The 2.4 GHz ISM band has become increasingly popular due the possibility for unlicensed multifaceted

applications to operate within this frequency band. Of particular interest for this investigation, in addition to

the spectral measurements, is to attempt to assess the effectiveness of this band and regulation in various en-

vironments. The research will examine the potential this band holds for additional applications and devices,

given the current span of devices and protocols currently operating within the frequency space. In short, the

goal will be to assess the effectiveness of such a frequency allocation and regulation.

The GPS L1 frequency band was one of the principle spectral allocations which impacted the resulting

regulatory power levels allowed for Ultra Wideband (UWB) emissions across the frequency span 960-1610

MHz [LAP00]. The GPS band is one identified where changes to incumbent rules are unlikely and would

be subject to heavy criticism. The potential interaction with GPS, and resulting theoretical and experimental

studies, resulted in minimal spectral overlay potential for UWB below 3.1 GHz. The GPS L1 signal is trans-

mitted within a designated aeronautical radio navigation service (ARNS) band, regulated under Aviation

Part 87, which is quite restrictive to facilitate safety/life critical services. The GPS signal is unique in that

it is a code division multiple access (CDMA) spread spectrum signal whose received power is below the

thermal noise floor for traditional receivers. Thus, reception and processing is sensitive to any additional

interference. The goal of spectral measurements within this band will be to extend past studies and inves-

tigate how effective this particular spectral allocation is being utilized as well as its sensitivities to existing

interference within the band.

In short, the goal of this component of the investigation is to provide a comprehensive study, via analysis

and measurements, of two diverse frequency allocations - and assess the effectiveness of their corresponding

regulation as well as how such allocations fit into the future of spectrum management. We will build on past

spectral measurement studies and references on conducting such measurements: [IEE86, IEE96, IEE01,

NTI95, NTI96, NTI97, NTI02, NAS03].

Physical Spectrum Exploitation While the longer term investigation provides insights into potential

bands, a transmitter that wants to communicate must make decisions based on short term measurements.

Figure 5 shows the dynamic nature of transmitters and interferers. The transmitter must consider not only

the success of its transmission, but also whether it will disrupt other transmitters. A fundamental problem

with measuring only transmitter signals is that interference occurs at the receiver and not the transmitter.

An underlay user can affect a sufficiently close receiver even when the licensed transmitter signal is strong.

Also, directional antennas can destroy the ability to correctly measure the interference environment. Further

study is needed as to the limits of what can be measured and exploited both individually and as arrays of

communicators.

Many of these problems can be solved by focusing on the licensed receiver. At present, however, there

are no rules on licensed receiver performance. Specific receiver performance requirements on sensitivity,

band filtering, etc. will open up additional underlay opportunities and provide a consistent model to judge

underlay interference potential. To that end, the FCC has not only opened up an investigation of the inter-

ference temperature concept, but also of the possibility of regulating receiver standards [FCC 03b]. Under

a regime of receiver standard regulation, active receivers could greatly improve the ability of underlay users

to detect potential interference situations. If a licensed receiver, for example, sent out a periodic low power

beacon, then the underlay transmitter could accurately measure the path loss between the underlay transmit-

ter and the licensed receiver and infer what communication could coexist with the licensed receiver.

Protocol Characterization Protocols such as ad hoc networks allow for a large number of nodes to collec-

tively communicate. Theoretical studies have shown that network capacity should increase with more nodes,

while emprical studies have shown marked reduction in capacity with more nodes. The gap between theory

and practice can be traced to the interaction between PHY, MAC, and Network layers and the distributed

communication agents acting in this environment. But, this interaction is not well understood. Simulation

and theoretical studies do not fully capture significant elements of these interactions. To address this gap,

the University of Colorado is developing detailed monitoring capabilities for ad hoc routing protocols in a

full-scale test bed for heterogenious, fixed, mobile, and airborne nodes. The monitoring tracks control and

Figure 5: Wireless spectrum monitoring conducted at Stevens Institute. Eachwaterfall plot shows activityover time and frequency. The highlighted sections on the left show interference from bluetooth wirelessdevices and a microwave source. The plot to the right shows a DSS spread-spectrum transmission in an802.11b network. Figures provided by Theodoros Kamakaris at Stevens Institute of Technology.

data packets as they traverse a network in real time. It also records position and other physical parameters

of the nodes. The data is archived and can be analyzed after the fact with a web-based GUI. An example

screenshot is shown in Figure 6. Currently the architecture monitors≈ 10 802.11b-based nodes running

DSR. The architecture can be extended to other protocols and more significantly can be ported to low-cost

nodes that will expand the scope and scale of the monitoring.

Protocol Exploitation The FCC is considering a number of overlay technologies that would allow unli-

censed users to communicate in licensed bands as long as they do not disrupt the primary user communi-

cation. Some protocol exploitation can be one-sided such as cordless phones that time their transmissions

between microwave oven power pulses. An overlay of TV signals might schedule its transmissions dur-

ing the blanking interval. Some might be centrally controlled such as a primary user that signals when it

will and will not be transmitting. Others might be cooperative where users negotiate transmissions using

some spectrum etiquette. Understanding what is achievable would benefit from more experimentation by

researchers.

Figure 6: An adhoc monitoring tool developed at CU that correlates node locations and routes (left) withperformance graphs (right).

F.2 Middleware for Spectral Management

F.3 Information Theoretic Interactions With Wireless Communications

It is well known that one of the least expensive methods to increase the return of investment for wireless

links is to improve the link capacity by means of using advanced error-correcting codes. For example,

reconfigurable, circular trellis turbo codes with QPSK data transmission were used as an FEC scheme for the

third generation (3G) wideband CDMA mobile telephony standard, performing within a 1dB margin to the

capacity limit. The application of FEC resulted in a system that required 5 dB less power, and was capable

of reliable transmission over a significantly increased coverage area. One of the major changes envisioned in

the 802.16 standard regarding signal processing and coding schemes is a switch from trellis-based encoders

and decoders, such as turbo codes, to block coding schemes based on sparse graphs. The most well known

representatives of the class of linear codes on graphs are Low-Density Parity-Check (LDPC) codes. The

802.16 reference model is predicted to involve joint dynamic modulation and LDPC coding with iterative

decoding (which may be optional), and a potential multipacket, variable packet length decoding scheme.

Implementations of LDPC codes in conjunction with advanced modulation techniques, such as Orthog-

onal Frequency Division Multiplexing (OFDM), are currently being investigated by many standard com-

mittees, as well as companies including Motorola, Intel, Flarion Technologies etc. The newly developed

broadband wireless chipset by Flarion Technologies is structured around a dedicated programmable paral-

lel processor that contains the description of a proprietary LDPC code. The Flarion technology has been

integrated into a mobile wireless communications system for end-to-end Internet Protocol-based mobile

broadband networking. The modulation schemes supported by Flash-OFDM include QPSK and 16QAM.

The coding rates currently used include rates 1/6, 1/3, 1/2, 2/3, and 5/6, and the system uses adaptive modu-

lation to rapidly switch between codes. The maximum data throughput offered in the Flash-OFDM system

is 3 Mbits/sec. This is currently the only commercially available chipset of this type.

There remain many unresolved design and testing issues regarding FEC methods for wireless channels.

Very little is known about the ability of reconfigurable LDPC coding schemes to adapt to multipath fading

channels with severe temporal variations in quality ranging over several tens of decibels. This is due to

the fact that codes are usually designed with fixed values for parameters such as code length, rate or struc-

ture. Performing an extensive testing of new and known coding schemes is a very time consuming task, if

performed by standard software Monte Carlo methods. Computing the error-floor of the codes, which is a

limiting parameter of the code performance for moderate to high SNR values, usually requires at least six

month of simulation time. Furthermore, if such an evaluation has to be performed for many code designs

in connection with many modulation schemes, the testing time may be prohibitively large. An alternative

to such testing methods is to devise fast FPGA and ASIC implementations of the coding and modulation

circuits. A part of the funds allocated to the project will be used to develop a hardware test platform for

evaluating the designed LDPC codes. The platform will be based on FPGAs, and will involve the embed-

ding of a LDPC decoder on a multiple FPGA die. Each FPGA will be floorplanned in a very regular manner

to maximize packing density and data throughput [30],[31], [39]. The computational units implementing

check and variable nodes will be designed as custom macro blocks, utilizing high-capacity FPGAs from

Xilinx. In addition to allowing for efficient testing of the coding and modulation systems, FPGA modules

offer an additional advantage of being easily incorporated into large communication systems.

The code design techniques itself will be centered around fully-parallelProgrammable Logic Arrays

(PLAs) with low wiring overheads. PLA-based designs have a very small chip size and power consumption

even for codes of large rate, and they offer a high level of operational flexibility. As an additional feature,

the proposed custom IC-based solution will have the property of on-the-fly reconfigurability between codes,

with significantly improved throughputs; initial experimental results show a decoding throughput of 25 Gbps

and a power consumption of about0.7W, for a code of length20000 and rates1/6, 1/3, 1/2, 2/3 and5/6with a die size 14mm on a side.

New Wavelet Applications: In the 4G communication system high bit rate transmission through mul-

tipath fading channels is aided by the use of OFDM. The OFDM scheme incorporates a guard interval for

eliminating intersymbol interference, which incurs a substantial loss in effective bandwidth. This reason

motivates the research on replacing the DFT-OFDM scheme by a Wavelet-based system. Wavelet trans-

forms allow for higher spectral containment between subchannels, therefore reducing the ISI level. Due to

the possibility of deep fades in wireless channels, the information of some subcarriers may be completely

lost. Hence, it is of crucial importance to incorporate an error-correcting code into the system. Very little

is known about the joint design and implementation of wavelet-based OFDM and iterative coding scheme.

Testing and modelling such systems may, again, be a very time consuming task for which specialized hard-

ware is needed.

Luby Transform Codes: One of the prevalent methods for distributing new software over the Internet is

multicasting or broadcasting. Unicast protocols based on receiver initiated repeat requests are unscalable and

hence do not represent an attractive solution for the problem. One acceptable solution is based on applying

erasure error-correcting codes for reliable multicasting. The principle behind most of such solutions is to

use “data carousels” or “data fountains”, where one transmits both information and redundancy packets. A

sufficient amount of redundant data packets can then be used to recover the missing information packets. In

order for such a scheme to exhibit a high level of flexibility, it is desirable to enable data reconstruction from

any sufficiently large subset of packets. This can be achieved by a class of codes termed Luby Transform

Figure 7: Signal Level from Phase Array Antenna

and a subclass of such codes, termed Tornado Codes. Both these types of codes represent a special form

of LDPC codes. Therefore, all the testing and implementation issues, in addition to some problem specific

constraints apply for this case as well.

F.4 Networking Challanges in Wireless Networks

Smart radios can negotiate modulation, coding, spreading, center frequency, timing, and many other char-

acteristics that may increase the efficiency of spectral use. Mutable media-access mechanisms, combined

with smart radios, can increase the temporal reuse of available spectrum by negotiating when spectral bands

should be used. Lastly, electronically controlled phase array antennas can increase spatial frequency reuse by

limiting the interference between communicating nodes. Despite the availability of these technologies, they

have mainly been applied in specialized, high-end communication systems that are expensive and compli-

cated to use. This limits the range of experimentation that is necessary to insure algorithmic breakthroughs

in spectral efficiency protocols, infrastructure and middleware.

Researchers at the University of Colorado have been experimenting with low-cost components that

allow a wide degree of experimentation in wireless networking protocols. These components include a

commercially available software-defined radio infrastructure, conventional wireless networks with mutable

MAC layers and inexpensive analog phase array antennas. These components provide a combination of

mutable PHY, MAC, and network layers that enable a wide range of experiments only recently possible.

Directionality in Wireless Networks Ad hocwireless networks are used for a combination of mobile

computing and fixed wireless applications. Fixed wireless installations, such as community networks, in-

frastructure for rural communities or temporary military networks, suffer from limited scalability when

commodity network standards are used with omnidirectional antennas [29]. Commercial scalable wireless

networks are typically constructed using a combination of directional and omnidirectional antennas arranged

to increase spatial reuse of the wireless media. Fixed directional antennas are inexpensive to purchase, but

the time and effort required to place and aim them appropriately is relatively high. This makes them less

desirable for temporary networks used by first responders or military applications.

Previous research using directional antennas has shown that problems arise when using a directional

antenna with a MAC layer, such as the CSMA/CA MAC uses in the 802.11 protocol, designed for omnidi-

rectional antennas. We have been conducting research on designing new MAC protocols to avoid the pitfalls

and take advantage of the features of new directional antennas. Unfortunately, modifying the MAC layer

means existing deployments of 802.11 equipment wouldn’t operate in such environments. Our results have

shown that simple additions to the existing MAC protocols can allow directionality to be exploited while

maintaining backwards compatability with existing equipment [32].

Our currently work has used a simulation infrastructure we developed under funding from NSF ANI

research. We integrated the Click modular router [28] into the NS-2 network simulator [33, 34]. In addition,

we developed antenna models that allow us to incorporate and control phase array antennas from within our

simulation environment. More recently, we have been using a prototype inexpensive phase array antenna

developed by a local company, Fidelity Comtech. This antenna provides varying antennas patterns, ranging

from a purely omnidirectional pattern to a 42 degree unidirectional beam in the 2.4Ghz range; the antenna

is connected to a commodity 802.11b networking card. Figure 7 illustrates data collected during Summer

2004 by Brian Mihok, an undergraduate student at the University of Colorado. That data shows the signal

strength measurement using the phase array antenna

Radio Competitions Spectrum regulation has relied on simple maximum transmit power, bandwidth, and

out-of-band limits with minor embellishments. Over time, radio complexity is growing and costs are de-

creasing. Radios are capable of operating under more sophisticated rules at reasonable costs to consumers.

For instance, receivers may be required to announce their presence using a known protocol. Or, communica-

tors in a band may be required to understand a simple etiquette that allows them to cooperatively negotiate

communication in a local area. But, widespread experimentation is lacking and we seek to provide the

hardware, software, and test bed tools to broaden the scope of researchers working on this problem.

Before such protocols can be adopted, it is necessary to characterize their effectiveness, the conse-

quences (intended or not) of their use, and understand how the protocols are enforced. When such evalua-

tion is complete, the regulators need to be persuaded that the protocols will work in practice. Much of the

characterization is possible through simulation or the building of a small number of radios. The challenge

will be to characterize the performance when many disparate users are simultaneously active. Game theory

can provide some insights, but, is unlikely to be predictive in the larger problem.

In short, a mechanism is needed to simulate the dynamic larger world situation of many potentially

competitive users using different technologies sharing a localized space. We propose to use an open ra-

dio competition. In other fields such as artificial intelligence (RoboCup [Rob04a]), and unmanned aerial

vehicles (Design, Build, and Fly [DBF04]), such open competitions have served multiple useful purposes.

First, they focus research on realizing practical gains. Second, they attract more researchers including un-

dergraduate and graduate students and industrial groups. Third, they accelerate the exchange of ideas among

researchers. Fourth, the merits and deficiencies of different approaches are more readily identified. Finally,

it raises the visibility of the research beyond the research community.

The radio challenges can be at different levels: software, common platform, and open platform. Soft-

ware competition will compete in a simulated environment similar to [Rob04b]. Candidate platforms would

include Opnet [Opn04], ns-2 [NS204], and OMNeT [Omn04]. The common platform competition will

compete using a readily available software defined radio hardware platform defined at CU. The open plat-

form competition will compete using any hardware and software combination that satisfies the competition

rules. The purpose of the different levels is to encourage participation even from groups with limited RF

engineering or hardware experience.

The University of Colorado will take the lead in organizing and promoting the competitions. It will

draw on its close ties with the National Institute of Standards and Technology–who have extensive facilities

for radio testing and measurement–and the Institute of Telecommunication Sciences–which is a scientific

advisor to NTIA on telecommunications and spectrum policy. ITS also runs the Table Mountain National

Radio Quiet Zone [TM04], a large outdoor radio testing area near Boulder with testing facilities and fiber-

optic Internet connectivity. The competition will start among the CU community. Once started, the goal will

be to develop the procedural, software, and hardware framework that can be migrated to other institutions.

G Educational Initiatives with the Proposed Equipment

Wireless communication has gone from simple AM and FM modulators to complex multi-layer architec-

tures. While the layers are a useful construct for decomposing the communication problem in general,

the challenges of the wireless physical layer permeate all the way up the protocol stack. Understanding

these coupled challenges is best achieved through a combination of lecture, demonstration, and hands-on

experience (i.e. hearing, seeing, doing).

H Participant Synergy

The proposal is comprised of faculty from Aerospace Engineering, Computer Science, Interdisciplinary

Telecommunications, Electrical and Computer Engineering. The personnel span a range of complementary

disciplines in theoretical and experimental wireless communications.

Dirk Grunwald , with a joint appointment between Computer Science and Electrical and Computer

Engineering, will be responsible for the overall success of the proposal. He has implemented wireless

protocols in hardware that span the physical, MAC, routing and application layers.

Dennis Akos, Aerospace Engineering, will be responsible for the spectrum allocation assessments and

measurements. His research contributes to the measurement methodology, the hardware platform develop-

ment, and the competition framework.

Tim Brown , with a joint appointment between ITP and Electrical and Computer Engineering, has devel-

oped a range of wireless hardware test beds from table-top emulation to a full-scale outdoor ad hoc network

test bed. He will oversee the student competition.

Greg Grudic, Computer Science, will work on applying statistical machine learning to wireless net-

works, including modeling and tracking of individuals in wireless networks.

Olgica Milenkovic, Electrical and Computer Engineering, will provide the theoretical underpinnings of

the communication models developed and demonstrated with the hardware.

Tom Lookabaugh with a joint appointment between ITP and Computer Science will be responsible

for an overall framework for using and measuring the success of the infrastructure developed under this

proposal in influencing commercial and other non-academic institutions.

Douglas Sickerwith a joint appointment between ITP and Computer Science, will (with Tom Look-

abaugh) focus on identifying key techno-social and commercially oriented problems - particularly as these

overlap with policy and regulatory issues - that can be quickly impacted by appropriate experiments.

The personnel on the proposal have worked closely on a number of past projects and have regular

interactions that cross the technology-policy boundary. Beyond the proposal personnel, the ready availability

of the equipment sought in this proposal will attract a wide range of researchers and students to cooperate

in wireless research.

I Leveraging the Infrastructure

The equipment acquired under this proposal will support five related research grants recently awarded to the

PIs. In all cases funding was cut 10–85% from the requested amounts. This proposal will provide a pool of

shared laboratory resources that will enable these grants to achieve much of their original scope.

The PIs also have active research funded under Homeland Security initiatives. These projects address

the mismatch between specialized expensive military hardware and ubiquitous low-cost commercial-off-

the-shelf (COTS) hardware. Having a pool of WIBBs will provide significant value in demonstrating COTS

wireless Internet capabilities and potential.

The PIs see significant potential for WIBBs to accelerate the transfer of wireless Internet technology

from the research lab into the commercial arena. Already the PIs have ties with industry ranging from

local startups, such as Fidelity-Comtech, to prominent new players, such as Vanu, to industry leaders, such

as Intel. The ability to more quickly demonstrate and deploy research technology with WIBBs will draw

greater industry interest toward academic research.

Through a number of initiatives, the University of Colorado is gaining prominence as a communication

policy center, sometimes denoted the “Colorado School” in the FCC. The ability to quickly demonstrate

technical consequences of proposed rulemaking using WIBBs will only further enhance this reputation.

The University of Colorado College of Engineering is nationally recognized for its commitment to

hands-on learning. The latest two buildings added to the engineering center were both conceptualized as

undergraduate laboratory and research centers. The WIBBs inventory will expand the scope of the type of

undergraduate research and provide a greater emphasis on emerging technology areas. These leading edge

technology tools will further raise the recognition for the college’s educational mission.

J Impact of Proposal

Communications impact on society is profoundly affected by policy and regulation or its lack. In line with

many previous technical revolutions, the information technology revolution is moving to a stage in which pi-

oneers for the most part seek sufficient intervention by authority to secure effective commercialization [36],

e.g., by addressing property rights and enforceability of contracts. Regulation is better if informed by good

technical insights. Increasingly, Key technical insights can be generated from inexpensive technology build-

ing blocks. This is encouraging, as it increases both the quality and diversity of input, including input from

investigators who are not significant commercial stakeholders in policy outcomes. We want to pioneer this

new stream of input into good policy making.

Inexpensive building blocks facilitate simple experiments to examine social implications of technology

- a necessary input to policy but also interesting in its own right. For example, ubiquity enabled by wireless

connectivity exacerbates technology driven shifts in what is perceived as reasonable and desirable privacy.

Particular experiments with informed participants can be quite illuminating; e.g., for what incentive would

an individual willingly concede elements of privacy. This can be extended to a wireless enabled example

- under what limitations and for what incentives would an individual agree to have his or her location

continuously logged?

Adoption of WIBBs in research can accelerate both the rate of innovation in non-academic settings (e.g.,

commercial, military) and the rate of transfer between academic and non-academic settings for wireless

technology. WIBBS are easily duplicated, lowering barriers to emulation, which generally accelerates the

rate of innovation across institutional boundaries. The key insights are in how WIBBS are assembled,

insight that can be quickly disseminated through electronic and traditional publication. We are interested

in pioneering this aspect of WIBB-based research to accelerate wireless innovation in the same way that

innovations in other areas of information technology (e.g., web services) have seen similar gains.

WIBBS shifts the research focus from the cost of the lab infrastructure to the external insights into

how to deploy it to answer interesting and timely questions. It opens the door to a more diverse set of

researchers who can push the boundaries of wireless communication. University of Colorado with its long

history of interdisciplinary research and the particularly interdisciplinary connections of this research team

is positioned to pioneer this style of research.

Part V

COORDINATION PLAN

The PI of this CRI proposal has been a co-PI on prior funded RI and CER proposals from the University

of Colorado. The management of our CER, CISE II, and current RI proposal have established a successful

management structure which we propose to use with only minor modifications. The modifications are

necessary because this proposal, unlike the prior proposals, spans two departments and involves a smaller

number of researchers. Despite this difference, we do not forsee significant management complications

since four of the five PI’s have been or are currently invovled in joint sponsored research.

The project will be led by a CRI Steering Committee consisting of the 5 PIs (Grunwald, Brown, Sicker,

Lookabaugh and Milenkovic). This committee will meet weekly to oversee the equipment and research

issues of the project. The staff members of the project (two lab technicians) will also attend these meetings.

The chair of the committee will be rotated among the PIs, with Grunwald serving as the chair in year one

of the project. Although the lab technicians will be technically supervised by the chair of the committee,

day-to-day supervision will delegated to faculty overseeing the development and installation of specific sets

of equipment.

One of the two main responsibilities of the steering committee will be deciding upon equipment pur-

chases. Two processes will be used, based on experience with current proposals. Since the proposal involves

the development of significant measurement and analysis infrastructure, there will be qaurterly allocation

of “working funds” to acquire and develop that infrastructure; this reduces the management overhead for a

large number of small purchases needed to assemble a larger system, but maintains tight fiscal constraints.

For major equipment purchases, a quarterly review and purchase program will be used. The committee will

consult with all faculty who are associated with the project, and formulate equipment purchase priorities,

including revisions, if any, to the original plan. The committee and technicans will then construct requests

for proposals, and after bids are received, lead a team that will evaluate the bids, following state-mandated

procedures. (Colorado law requires a competitive bidding process, but leaves considerable flexibility in

constructing the evaluation criteria. Sole source purchasing is sometimes permissible.) Evaluation of bids

will include on-site tests of proposed equipment.

Once new equipment is received, its installation and maintenance will be the responsibility of the project

technicans, or installation will be contracted with the computing operations staff of the Department of Com-

puter Science. Much of the equipment will be assembled in the hardware lab, but will be used in various

project’s laboratories.

Network facilities will be used throughout the Engineering Center. Additional highspeed networking

will be added to the building to facilitate data collection using an existing fiber optic cable plant. The

development and deployment of this network will be based on the highly successful deployment of gigabit

Ethernet in the Computer Science department, led by Dr. Grunwald.

All of the equipment of this project will become part of the joint Department’s overall research facility

and be accessible to all research faculty and staff, with priority given to project members.

The other major responsibility of the steering committee will be monitoring and guiding the progress of

the proposed research. The PIs will have responsibility for their individual research projects; the committee’s

emphasis, in addition to seeing that the projects have adequate equipment resources, will be coordination

among these projects. This will occur in two main ways: First, at least half of the weekly committee

meetings will focus on joint research (with the remainder focusing on equipment purchases); these will also

be attended by key research assistants on the projects, and will serve as a forum to give updates on research

progress and discuss interesting research issues. Secondly, once every three months, a half or full day retreat

of the entire project will be held where all project members will discuss recent research issues in more detail,

discuss strategy for the main next steps in the project, and explore new opportunities for collaboration.

Part VI

Bibliography

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[14] Robert Cooksey, Stephen Jourdon, and Dirk Grunwald. A stateless, content-directed data prefetching

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layer mechanism for fairness in 802.11 networks. InFirst International Conference on Broadband

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[17] Keith I. Farkas, Jason Flinn, Godmar Back, Dirk Grunwald, , and Jennifer Anderson. Quantifying

the energy consumption of a pocket computer and a java virtual machine. InProceedings of the ACM

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2000. (to appear).

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dynamic clock scheduling. InOperating Systems Design and Implementation, San Diego, CA, Oct

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Boulder, December 2002.

Facilities

This proposal will use the facilities of the University of Colorado Department of Computer Science, Depart-

ment of Electrical and Computer Engineering and the Interdisciplinary Telecommunications Program.

The engineering school has built one new building in 1997 (the Integrated Teaching and Learning Lab)

and in September 2002 completed a new building committed to research (the Discovery Learning Center).

This DLC houses the Pervasive Communication Lab. This lab studies densely interconnected networks,

low power wireless devices, and limits of networked communication. This lab consists of RF test and

measurement equipment, industry standard radio system design tools, a dozen 802.11b equipped laptops

and PDAs, and a hardware testbed that allows us to emulate wireless network scenarios in a controlled

environment. A current focus is the development of energy aware ad hoc wireless protocols based on

LINUX and 802.11b

Electrical and Computer Engineering and Interdisciplinary Telecommunications will provide the office

space and basic infrastructure for the program. The ITD has multimillion-dollar telecommunication labs

with state-of-the-art routers, switches, network performance testers, RF and cellular system measurement

equipment, and network, cellular, and satellite system modeling software.

Computer science has an NSF RI funded Tera-flop computing farm available for simulation work. It

also has a $2M NSF RI titled “Digital Common Spaces” which funds a variety of wireless networking

equipment including experimental indoor and “last mile” wireless prototypes. They have research groups

working on RFID, sensor network, and ad hoc wireless network technologies, that adds equipment, facilities,

and expertise for this proposal.

Part VII

BUDGET JUSTIFICATION

The budget for this proposal consists of money for equipment and money for students to manage the equip-

ment and to prepare it for use in the research and education roles. Unlike prior Research Infrastructure

proposals at the University of Colorado, this equipuipment will be managed by students rather than a dedi-

cated support staff, because portions of the equipment need to be constructed from purchased components

and other systems need to be designed and built.

The students building the RF front-ends for the monitoring system will be led by a pair of graduate

students each with 25% appointments. This arrangement was chosen so that students could be overlapped

and staggered over time to maintain continuity of the management function over time. This arrangement

has proven satisfactory in other student laboratory management roles. The budget also includes funds for

undergraduates who will assemble components for educational applications.

Lastly, an additional graduate student research-assistant ship is budgeted for the first two years from

matching funds; this student is responsible for developing the high speed monitoring system, including the

development of the Xilinx components, the boad design for the interface and the protocol development.

The equipment is largely divided into measurement and building block components. The measurement

components are listed in the table below.

Agilent 8562EC Spectrum Analyzer

• 30 Hz – 13.2 GHz capabilities with signal identification and

phase noise measurement capabilities

$40k

Preamplification and Frequency Selective Components

• low noise amplifiers, cavity filters, switches$8k

RF Cabling and Adapters $5kAntenna Elements

• directive high gain, broadband, multi/element array, and om-

nidirectional varieties; motion control for directive antennas

$23k

Commercial Receiver Elements

• GPS receiver(s) with automatic gain monitoring capabilities,

various 2.4 GHz devices (WiFi, Bluetooth, Cordless tele-

phones/cameras)

$17k

Accessories

• Power conditioning, thermal monitors, remote power sup-

plies

$7k

Total $100k (est)

The measurement equipment is supported by a Gigabit ethernet equipment and a computing cluster

consisting of the equipment in the following table.

Gigabit Networking Components

• Two fiber gigabit routers, fiber cables,etc

• Eight data collection systems, 2-3TB of disk, highspeed in-

terface.

$60k

Computing Cluster

• 32 networked 3GHz Linux nodes

• Gigabit network interfaces, switching fabric for connection

to data collection system

$60k

Total $120k (est)

The radio components consist of building blocks, software controlled radios, and software defined radio

equipment as listed in the table below.

Comblock Components

• RF front ends, modulators, baseband processors$40k

Antenna/Front-End Toolbox

• Includes various elements not used in the measurements

campaign: antennas, discrete components for the construc-

tion of a superheterodyne front end designs, GNU Radio Mi-

crotune evaluation board(s)

$20k

Analog-to-Digital & Digital-to-Analog Converters (ADC & DAC)

• Standalone ADC & DAC evaluation boards, PC-based data

acquisition boards

$13k

Low-cost Linux based radios

• 100 Linksys WRT54G or similar boards$7k

Fidelity Comtech 8-Element Steerable Antenna Array

• 10 2.4GHz ISM band with host PC control$30k

Agilent 89641 Vector Signal Analyzer

• Single RF channel, 20 MHz - 6 GHz tuner module, software

demodulation, host PC control

$50k

Agilent 4438C ESG Vector Signal Generator

• Single RF channel, 250 kHz - 6 GHz tuner module, 80MHz

RF BW, host PC control

$25k

Digital Interface Components

• Data bridges between the digitizing and computational ele-

ments, USBv2, Firewire/1394, FPGA-based PC data buses

$15k

Signal Processing Elements

• Reconfigurable hardware for the implementation of SDR

algorithms: FPGA, DSP, and Microprocessor development

environments

$25k

Total $225k (est)

The total capital equipment requested is $435k, and the total capital equipment budget (including match-

ing support from the University of Colorado) is $480,000. The remaining capital eqiupment funds will be

used to compensate for the unexpected expenses that usually arise in constructing large systems such as this.

J.1 Matching Funds

The NSF funding of $800k will be matched by $160k from the University of Colorado. Part of that funding

will be used to provide a graduate or research associate to develop specialized measurement boards to

interface to the ComBoard measurement system. Additionally, we have budgeted fabrication costs for those

systems and additional non-captial materials costs (e.g.antenna’s, cases, cabling and the like).

Lastly, we have budgeted for three international trips to continue collaboration with researchers at Up-

psala University, TU Munich and Geneva. Dr. Brown spent a research sabbatical at Uppsala, Sweden in

2004, and Dr. Akos was a visiting professor at Lulea University, Lulea, Sweden. Dr. Brown also has an

on-going research relationship at TU Munich, including the exchange of students and faculty visits. These

Universities are premier instutiions in software defined radio, and these trips will help to recruit graduate

and post-doctorate students.