White Paper: Applications, Technology and Benefits for ... · xG White Paper: xMax Overview—Applications, Technology and Benefits for Public Utilities 4 xMax Mobile Voice and Data

White Paper:

xMax Overview—Applications, Technology and Benefits

for Public Utilities

March, 2014

xG Technology, Inc. proprietary and confidential, copyright

2004—2014. Patents are pending on portions of this system.

No part of this document may be disclosed, copied, or used

for any other purpose without prior written consent from xG

Technology, Inc.

xG Technology, Inc.

7771 West Oakland Park Blvd.

Suite 231

Sunrise, FL 33351

www.xgtechnology.com

xG White Paper: xMax Overview—Applications, Technology and Benefits for Public Utilities

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TABLE OF CONTENTS

CURRENT SITUATION ......................................................................................................................................................................... 3

XMAX MOBILE VOICE AND DATA OVERVIEW .................................................................................................................................... 4

XMAX NETWORK COMPONENTS ....................................................................................................................................................... 4

KEY XMAX CAPABILITIES AND SUPPORTING FEATURES ..................................................................................................................... 5

CAPABILITY: INTEGRATED IP-BASED CELLULAR NETWORK FOR VOICE, DATA, CHAT AND VIDEO .................................................................................... 5

Supporting xMax Feature: End-to-end IP architecture and shared spectrum optimization ............................................................. 6

CAPABILITY: COGNITIVE OPERATION INCLUDING DSA AND INTERFERENCE MITIGATION............................................................................................. 6

Supporting xMax Feature: Advanced cognitive sensing, signal and multi-spatial processing ......................................................... 6

CAPABILITY: EXTENDED RANGE, RELIABILITY AND THROUGHPUT WITH LOW POWER CONSUMPTION ............................................................................ 6

Supporting xMax Feature: Advanced antenna, PHY layer and software radio design ..................................................................... 7

CAPABILITY: INTERFERENCE TOLERANCE, FREQUENCY REUSE AND HIGH LINK RELIABILITY ........................................................................................... 7

Supporting xMax Feature: MIMO, powerful DSP processing and advanced software design ......................................................... 7

CAPABILITY: XMAX SUPPORTS COTS END USER DEVICES .................................................................................................................................... 8

Supporting xMax Feature: xMod protocol bridge ............................................................................................................................ 8

CAPABILITY: NETWORK SCALABILITY AND FLEXIBILITY ......................................................................................................................................... 9

Supporting xMax Feature: xAP clusters, transmit/receive synchronization and DSA ....................................................................... 9

CAPABILITY: EMERGENCY COMMUNICATIONS SYSTEM ....................................................................................................................................... 9

Supporting xMax Feature: Rapid-deployment emergency response/remote service system ........................................................ 10

SUMMARY ....................................................................................................................................................................................... 10

ABOUT XG TECHNOLOGY ................................................................................................................................................................. 11


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Current Situation

In order to improve their operational efficiency and reduce costs, public utilities are recognizing the need to

transition their current communications infrastructures to more advanced and flexible alternatives. While

some have already started adding digital communications and monitoring systems to their production,

transportation and distribution systems, there remains a critical need to optimize the limited bandwidth they

have at their disposal to support their wireless networks and mobile communication applications.

Cognitive, or smart, radio technology can offer utilities a wireless solution that will meet their operational

requirements, while providing enhanced service capabilities for wide-area communications with mobile

workers, emergency response deployments, smart grid infrastructures, telemetry and monitoring. This smart

technology will allow devices to quickly and efficiently detect available frequencies and use only those that are

able to provide reliable end-to-end communications.

xG Technology has developed an all-IP, affordable mobile voice and data cellular system called xMax that

operates in free unlicensed bands. Using a patented cognitive radio core technology and advanced system and

signal processing capabilities, the xG system makes unlicensed spectrum communications as reliable as

licensed band communications. This is made possible by effectively mitigating the interference in the

congested and chaotic unlicensed bands.

Among the benefits for utilities employing the xMax cognitive radio network are efficient and low cost service

delivery compared to traditional cellular infrastructures, reliable real-time communications with smart meters,

and low-latency connectivity without the expense of licensed spectrum. This is a solution that meets utilities’

smart grid requirements while supporting their key applications such as SCADA, mobile voice, mobile data,

security and surveillance.


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xMax Mobile Voice and Data Overview

xMax is a mobile voice and data solution from xG Technology that has been designed to address the issues

raised above and more. In particular, it was created with the following requirements in mind:

Leverages COTS end user devices including 3G and 4G smartphones, tablets and netbooks without

requiring licensed commercial frequencies.

Dynamic Spectrum Access (DSA) and advanced interference mitigation to increase operational and

deployment flexibility.

Full cognitive networking capabilities including dynamic access and optimization of available spectrum

resources, as well as self-Radio Frequency (RF) planning and self-organizing.

A single end-to-end IP network architecture supporting mobile voice, wideband data, real time video, chat

and other apps.

xMax Network Components

The following diagram depicts provides a high-level overview of the xMax network architecture with the

integration of common utility applications.

Figure 1 – xMax Network Architecture


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The xMax solution leverages a standard cellular architecture – with some notable enhancements. The

following are the major components of the system:

xMod: the xMod is a small radio that bridges the COTS end user device to the

wideband transport layer of the xMax system. Devices may be physically

tethered or connected via secure WiFi links to the xMod. The xMod can deliver

up to 1 to 2 Mbps to the connected end user device(s) under real world

conditions

xAP: the xAP acts as a compact, high-performance base station and wirelessly

connects to the xMod using the xMax cognitive networking waveform. Each xAP

can deliver up to 2 Mbps of total user bandwidth to its associated xMods. xAPs

may be deployed individually or in clusters of up to 9 xAPs to increase total

throughput.

xMSC: the xMSC acts as both a base station controller and aggregation point for the connected

xAPs. It performs routing and security functions, as well as proprietary mobile VoIP optimization

and compression. The xMSC is typically connected to the worldwide Internet and one or more

VoIP soft switches.

xMonitor/xDrive: these software tools provide

integrated and comprehensive network and element

management for the xMax network, as well as mobile

network throughput and coverage optimization.

Key xMax Capabilities and Supporting Features

Capability: Integrated IP-based cellular network for voice, data, chat and video

All voice, video, data (including geo-location info) is carried on a single integrated xMax network. Unlike other

4G networks that require separate networks for voice and data, xMax delivers a truly unified transport layer.

Its all-IP architecture leverages COTS routers and switches in place of proprietary, expensive network


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infrastructure used in other mobile networks. Common IP-based apps (all smartphone and computer apps)

are supported over the network, while integration with legacy systems is greatly simplified.

Supporting xMax Feature: End-to-end IP architecture and shared spectrum optimization

All the components of the xMax system are IP based. COTS routers and switches are used as network

components. The xMax xAP supports both Ethernet and Fiber interfaces. Voice is transported as

mobile-optimized Voice over IP (VoIP), enabling the entire system to operate as a data packet network

– but with full voice calling features. Standard SIP signaling supports integrated COTS voice switches

and gateways, or an external (cloud-based) switch/gateway service may be utilized.

The air interface between the xMod and xAP is an advanced Physical Layer (PHY) featuring OFDM

modulation and MIMO transmit and receive. This interface, combined with other xG innovations, was

optimized to provide licensed quality service in free, unlicensed spectrum. Since this is a shared

spectrum resource, implementing interference immunity and spectral efficiency was paramount for

commercial applications.

Capability: Cognitive operation including DSA and interference mitigation

xMax employs advanced cognitive radio and networking techniques, including Dynamic Spectrum Access to

provide reliable operation in unlicensed but interference prone spectrum. xMax’s Dynamic Spectrum Access

technology is frequency agnostic and can be re-tuned to operate in TV white spaces, unlicensed or licensed

commercial bands. Another benefit of xMax’s cognitive technology is that the network has the ability to self-

configure and self-organize. This is planned to be further enhanced to support full meshing capabilities in

future xMax product releases.

Supporting xMax Feature: Advanced cognitive sensing, signal and multi-spatial processing

Real time RF sensing and dynamic spectrum access are the

cornerstones of xMax radio technology. The commercial xMax system

utilizes the 902-928 MHz band for license free operation. Using this

freely available band allows the xMax system to scan over 16 channels

for interference-free operation. Both the xAP and xMod devices are

frequency agile and have several built-in capabilities to mitigate

interference by first employing advanced signal/spatial processing as

well as dynamically switching channels to avoid overwhelming

interference or jamming.

Capability: Extended range, reliability and throughput with low power consumption

xMax uses a state-of-the-art Physical Layer implementation that maximizes range and reliability while

minimizing power consumption. The system continually self-adjusts to optimize the wireless communications

link. It was also designed so that end users and network infrastructure are capable of high mobility. The

Figure 2 – Dynamic channel selection


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patented technologies incorporated to support these capabilities also enable xMax to minimize power

consumption and maximize battery life while maintaining robust and secure connectivity.

Supporting xMax Feature: Advanced antenna, PHY layer and software radio design

The xMax PHY layer is designed with a proprietary 2x4 (two transmitters, four receivers per link)

multiple input multiple output (MIMO) antenna and radio configuration. This MIMO system enables

longer range, higher throughput and is a key enabler of the xMax interference mitigation technology.

Maximal Ratio Combining (MRC) and multi-spatial receive diversity is utilized over the 4

receivers/antennas to provide over 5 dB gain over non-MRC receivers.

The system uses orthogonal frequency division modulation (OFDM) which is found in other state-of-

the-art wireless systems such as LTE, WiMAX, WiFi and other 4G+ solutions. The OFDM carrier spacing

and channel bandwidth are designed so that end user mobility is supported to over 65 mph. The xMax

system utilizes proprietary long OFDM symbols, which allow longer cyclic prefixes. This results in low

overhead and high usable throughput (as a percentage of total over the air bandwidth). The long prefix

design increases immunity to multipath interference found in harsh terrain and urban canyons.

The xMax PHY supports adaptive modulation with BPSK, QPSK, QAM16 and QAM64 modes that allow

the system to dynamically self-configure for the optimal combination of range, throughput and

interference rejection.

This combination of capabilities enables increased performance under dynamic conditions, in addition

to minimizing power consumption for extended battery life and remote operation.

Capability: Interference tolerance, frequency reuse and high link reliability

By applying cognitive capabilities to enhance active interference mitigation (in addition to DSA), xMax can

operate effectively under higher interference and jamming levels than competing solutions. This is critical for

maximizing reliability as well as increasing the utilization of scarce spectrum resources. By enabling xMax to

tolerate high levels of interference before requiring the radios to switch channels, more “gray spectrum”

(spectrum containing interference or jamming) can be used in place of white spectrum (clean and

interference-free spectrum). This capability increases the network’s total throughput and capacity greatly –

without consuming additional scarce spectrum resources. Since the technique is primarily implemented within

the receiver chain, the RF environment is not made noisier as would be the case for mitigation techniques that

rely on raising the transmitter power to overcome the interferer. This technique significantly increases the

system capacity of an xMax network.

Supporting xMax Feature: MIMO, powerful DSP processing and advanced software design

The xMax system employs a new and powerful parallel processing DSP/CPU unit that supports speeds

up to 50 GOPS (billion operations per second) for signal processing. This capable processor, combined

with the 2x4 MIMO antenna configurations, enables the xMax system to use patent-pending spatial

processing software to remove unwanted interference from the target signal. Each xMax cognitive


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radio can simultaneously mitigate interference from up to 24 mobile sources of interference or

jamming.

Figure 3- Spatial Processing to mitigate jamming and interference

Capability: xMax supports COTS end user Devices

xMax uses a unique approach to integrate (COTS) devices into its all IP network via the xMod wireless bridging

device. By being device agnostic, platforms, OS (operating system) and apps can be refreshed and sourced

from third party vendors quickly with no additional integration or software development required. Training

and complexity are also reduced since familiar devices and interfaces can be seamlessly incorporated into the

xMax network.

Due to the system’s inherent scalability and affordability, xMax and connected COTS devices can be widely

deployed. The same smartphone can be used in office or campus networks or in cellular mobile wide area

networks.

Supporting xMax Feature: xMod protocol bridge

The xMod is a WiFi (or USB tether) to xMax protocol bridge. Using an

advanced signal processor, xMod provides the DSA and interference

mitigation capabilities of the xMax wideband transport layer at the

network edge. This approach not only makes the system device agnostic,

but also operating system OS agnostic as well. The xMod supports

voice, data, video, chat and other applications on any WiFi or USB

capable device.

Figure 4- xMod protocol bridge

Wi-Fi network or USB tether

xMod


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Capability: Network scalability and flexibility

The xMax system offers cost-effective scalability for capacity, performance and uplink/downlink bandwidth

shaping. By employing a building blocks approach to network configuration xMax network nodes can be

configured from 2 Mbps to 32 Mbps of capacity. The system also uses a flexible TDD time slotted MAC layer.

This MAC has configurable uplink and downlink areas so that network uplink and downlink bandwidth ratios

can be set for specific applications such as web surfing, video conferencing and or voice/text conversations.

The xMax system is designed with size, weight and power & cost (SWAP-C) in mind. Network access points

can be mounted on non-optimal sites for easier network deployment due to their small size and weight.

Ethernet or fiber interfaces are provided to connect the infrastructure to the operator’s backhaul network of

choice.

Supporting xMax Feature: xAP clusters, transmit/receive synchronization and DSA

Network node capacity can be scaled from one xAP (up to 2 Mbps) up to a cluster of 16 co-located

xAPs (32 Mbps). All xMax xAPs are time synchronized either by GPS or NTP. This enables co-location of

multiple xAPs and the ability to use all available channels without causing adjacent channel

interference, unlike non-synchronized systems. All radios transmit and then receive in unison, which

reduces or eliminates self-interference in the network. This enables xMax to utilize 100% of available

channel capacity within the network. The xAPs scan and use the “best” channels out of the pool of over

16 channels in release 3.0, with more spectrum bands can be added in future releases. Each radio does

this continuously and automatically to maximize throughput.

Having 16 accessible channels allows neighboring network nodes (made up of one or more xAPs) to

utilize non-interfering channels automatically. This allows the system to grow and scale easily without

redesigning the network RF plan each time a device moves or when xAPs or users are added or

removed from the network.

Capability: Emergency Communications System

As we have seen in recent disasters where communications infrastructures have been destroyed or severely

impaired, current wireless network solutions have fallen short of providing and maintaining the levels of

coverage and capacity needed. There are significant complexities involved in rapidly restoring communications

capabilities and electric power immediately following a catastrophic event. These include not only deploying

the equipment that will be involved in establishing interoperable emergency communications for first

responders and utility operations, but also the problems associated with frequency coordination and the

potential for harmful interference.


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Supporting xMax Feature: Rapid-deployment emergency response/remote service system

xMax is designed to deliver a high level of resilience and continuity of operations,

enabling a self-contained, fully mobile “telephone-in-a-truck” response platform

following either natural or manmade disaster event. xMax features broadband

access points that can be combined with satellite links to operate provide voice

video and data connectivity back to the Internet and surrounding command

centers, enabling seamless communications between, local, state and federal

command structure and systems. This interoperable rapid deployment concept has

already proven itself in U.S. Army field trials conducted during major exercises in

2011. Personal or vehicle mounted xMax bridges are used to connect any smart device, such as

headsets, laptops, tablets, etc. to the core xMax cognitive radio network via a local Wi-Fi, USB, or

Ethernet connections. The ability of xMax to restore voice, video and broadband data services in the

“golden hour” after a disaster, without requiring, or interfering with, commercial mobile networks, is a

key benefit.

Summary

As utilities seek to cope with a spurt in bandwidth-intensive traffic resulting from growing data loads, smart

grid implementations and other demands on their systems, there will be increased pressure to ensure their

wireless communications infrastructure can keep pace. The xMax cognitive radio cellular system from xG

Technology represents a complete, scalable mobile wideband solution that is capable of delivering the

advanced communications, unified architecture support and operational efficiencies required. The system has

been deployed and demonstrated in disparate settings including a military environment at Fort Bliss and at

rural cellular operator sites in Florida and Arkansas. This flexibility to serve disparate markets stems from the

xG Technology affordable and rapidly deployable all-IP architecture.

While xMax incorporates several state-of-the-art and proprietary technologies such as dynamic spectrum

access and multi-spatial interference mitigation, it also leverages COTS end user devices including 3G and 4G

smartphones, tablets, netbooks, etc. These advanced features increase operational and deployment flexibility

while also improving the utilization of scarce spectrum resources

The xMax system’s cognitive networking capability allows it to dynamically access and optimize available

spectrum resources, while also enabling it to optimize its own RF plan. Future software releases will enable an

automatically self-organizing network (SON) in direct support of xMax’s operation as a mobile ad hoc network

(MANET and MESH).


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Finally, its end-to-end IP network architecture supports mobile voice, wideband data, real time video, chat and

other apps over a single integrated network, unlike typical 3G and 4G networks that require separate voice

and data network equipment and transport layers.

For all these reasons, public utilities seeking to migrate their existing systems to one that is designed to

support their requirements today as well as tomorrow will find that xMax represents a practical and attractive

technical solution.

About xG Technology

xG Technology is a leading developer of innovative and disruptive communications technologies for wireless networks. Its extensive patented intellectual property portfolio covers a broad range of applications including cognitive radio networks. The company has commercialized some of these technologies to create xMax, the world’s first carrier-class cognitive radio network.

xMax’s standards-based IP architecture minimizes network deployment, management and operational costs while simplifying the delivery of fixed and mobile services. Using field-proven cognitive radio technology, xMax enables the delivery of mobile services in both licensed and unlicensed bands.

xMax offers unique capabilities to enterprises, utilities, government agencies and others who require advanced wireless communications to support business operations and mission critical applications.

xG Technology offers turnkey xMax network solutions including base stations, mobile switching centers, network management systems, deployment tools, handsets and customer support.

xG has deployed four networks in the field that showcase xMax’s cognitive radio, mobile VoIP, and dynamic interference mitigation capabilities. These include a trial network at the US Army’s base at Fort Bliss, Texas and White Sands Missile Range; two rural deployment trial networks with Townes Tele-Communications, Inc.; and a 32 square mile urban/suburban xMax network in Fort Lauderdale, Florida.

Based in Florida, xG Technology has 60 US and more than 130 international patents and pending patent applications. For more information, please visit www.xgtechnology.com.

http://www.xgtechnology.com/

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White Paper: Applications, Technology and Benefits for ... · xG White Paper: xMax Overview—Applications, Technology and Benefits for Public Utilities 4 xMax Mobile Voice and Data