Software-defined radio and JTRS

Dec. 1, 2004
The U.S. military's next-generation radio system is to be based on software-defined radios, which will enable one radio to communicate with several radio networks, no matter the type of radio, whether it be SINCGARS or a satellite terminal.

The U.S. military’s next-generation radio system is to be based on software-defined radios, which will enable one radio to communicate with several radio networks, no matter the type of radio, whether it be SINCGARS or a satellite terminal.

What we have here is a failure to communicate,” said the late character actor Strother Martin in the 1960s film Cool Hand Luke. He was addressing a chain gang in a prison.

The same could be said of military radio systems during the last few decades. Soldiers were only able to communicate with each other in battle if they had the same types of radios.

Those using the latest SINCGARS (single-channel ground and airborne radio system), for example, often were unable to communicate directly with others using even the most modern satellite communications (SATCOM) systems.

The inability of different types of radios to work together causes problems not only among coalition and allied forces, but also among the various elements of the U.S. military itself.

Not to worry. Some of the finest minds in defense and industry are solving the interoperability problem with the Joint Tactical Radio System (JTRS). JTRS is a software-defined radio (SDR) that will enable soldiers to communicate with a wide variety of new and existing communications systems, as well as help older radios network with one another.

The JTRS program plans to replace the traditional hardware radios currently deployed with devices that can emulate any radio’s capabilities by simply changing software. Fielded JTRS radios can be upgraded with new software via the wireless information network. This ability to insert emerging technology into the JTRS system paves the way for broadening the radios’ performance and creating new applications such as sensors for signals intelligence.

The $1 billion JTRS network will replace stovepipe radio-frequency communications with software-defined radio in the 2-MHz to 2-GHz spectrum, with room for growth to frequencies above that. Battlefield commanders will use the new network to trade voice, data, and video between aircraft, ocean vessels, and land stations worldwide.

Software-defined radio

U.S. Army leaders say an SDR is similar to a computer; users can tailor the capabilities of its relatively generic hardware with software waveform applications. A software-defined radio can accommodate various physical-layer formats and protocols, convert analog radio signals into digital data, which it processes with software running on a microprocessor. Software controls frequency, modulation, bandwidth, security functions, and waveform requirements.

“Software radios have the flexibility to allow incorporation of new functionality into the system, without having to upgrade or replace hardware components,” according to army descriptions. “Multiple software modules allow implementation of different standards in the same radio system (including the capability to have multiple waveforms resident on the same set). Because radio receivers can be reconfigured over the air, there are decreased maintenance requirements.”

A Joint Tactical Radio comprises waveforms, radio hardware, and associated operating environment, which conform to the Software Communications Architecture (SCA).

Rockwell Collins is supplying hardware for the JTRS Cluster 1 as part of the Boeing team.
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The SDR will receive a particular waveform - an old one such as SINCGARS, or a new one such as JRTS - and then pull up the waveform to match the received signal, much like someone would pull up Microsoft Word. The SDR, however, must be a lot more reliable than a PC, says Bruce King, vice president and general manager for the Rockwell Collins Communications Sector in Cedar Rapids, Iowa.

Rockwell has 18 to 32 of the waveforms for JTRS Cluster 1 - old and new, King says.

Rockwell’s Wireless Wideband Networking Engine (WNE) is evolving toward the Wideband Network Waveform (WNW) requirements. WNE complements multiband JTRS radios and enables the user to deploy and use available spectrum - even noncontiguous, different-sized channel bandwidths, Rockwell officials say. Rockwell Collins WNE testing has demonstrated wideband lower Tactical Internet (platoon to battalion) connectivity for land-based platforms and airborne relay, company officials claim.

Rockwell Collins is part of the Boeing-led team JTRS for the Airborne and Maritime/Fixed Station (AMF) Cluster, and is responsible for the radio design, fixed-site radio integration, and platform integration support for the pre-system development and demonstration phase.

Rockwell is also part of the Cluster 5 program to develop a small man-portable JTR. The main challenges under Cluster 5 are weight, power, and thermal issues due to the small size, King says.

Software Communications Architecture

“Governments worldwide are adopting the SCA, which was developed under the auspices of the JTRS Joint Program Office,” say Spectrum Signal Processing officials in Burnaby, British Columbia. “The SCA provides a core framework to enhance portability of military waveforms across disparate radio architectures.”

The open-architecture SCA framework tells designers how to blend hardware and software within the JTRS, according to the JTRS Web site. The SCA governs the structure and operation of the JTRS, helps programmable radios load waveforms, run applications, and network into an integrated system. Design engineers use the SCA definition document just as an architect or planner uses a local building code to design and build homes. All JTRS components must be SCA compliant.

The flexComm SDR-3000 MRDP platform from Spectrum Signal Processing integrates Spectrum's SDR-3000 with a DRT-2110 radio-frequency (RF) front-end transceiver from Digital Receiver Technology.
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Spectrum engineers released a new SCA-enabled platform called the flexComm SDR-3000 MRDP, a MILCOM Rapid-Proto­typing Development Platform. This is the industry’s first “RF to Ethernet” commercial off-the-shelf (COTS) solution for military communications programs, Spectrum officials claim. This platform integrates Spectrum’s SDR-3000 with a DRT-2110 radio-frequency (RF) front-end transceiver from Digital Receiver Technology Inc. (DRT) in Germantown, Md.

The SDR-3000 MRDP provides a turnkey black-side processing system for JTRS and other MILCOM developers. This system includes sample application software supporting frequency-agile operation, and is for rapid prototyping and wide- and narrow-band waveform development, Spectrum officials say. Additional benefits and features of this platform can be found at sdr_3000.asp.

“Using a turnkey system such as the SDR-3000 MRDP is expected to save our customers months of integration effort, even if they are already familiar with the individual components,” says Mark Briggs, Spectrum’s director of marketing. “This platform, when combined with the training, support, and example applications with source code that Spectrum provides, may be the critical difference between a MILCOM development team hitting or missing their project milestones.”

Combining our compact, ­frequency-agile RF transceiver with Spectrum’s subsystem running an SCA core framework provides a scalable solution that should appeal to JTRS waveform developers and others doing multichannel MILCOM applications,” says Frank Hannold, manager of applications engineering at DRT.

The SDR-3000 MRDP includes Spectrum’s SDR-3000 Software Defined Radio processing and analog-to-digital converter/digital-to-analog converter boards (PRO-3100, PRO-3500, ePMC-8311 and TM1-3300) in a four slot 2U CompactPCI chassis. These components are integrated with the DRT-2110 RF transceiver subsystem consisting of four cards (RFT2, TEX, REF2 and CTRL12 single-board computer) in a 21-slot 3U CompactPCI chassis.

The system includes all software application libraries, including digital downconversion and digital upconversion FPGA cores, operating systems, and an SCA core framework. A working software dataflow example demonstrating a frequency-shift-keying (FSK) modulation and demodulation application presents a starting point for customers’ design efforts, Spectrum officials say.


Field-programmable gate arrays, or FPGAs, are also playing a significant role in improving the efficiency of SDR and thus the JTRS program.

“Reconfigurable computing will play a very significant role in JTRS, especially as bandwidth and data throughput continue to increase,” says Manuel Uhm, DSP marketing manager at Xilinx Inc. in San Jose, Calif. Uhm is also co-chair of the Marketing Committee of the SDR Forum ( “Sophisticated waveforms, such as WNW (Wideband Networking Waveform, the new JTRS waveform) and MILSATCOM waveforms and data links, require the parallel processing of FPGAs to perform most of the signal processing, as digital signal processors and general-purpose processors lack the necessary performance.

“It is no exaggeration to say that reconfigurable computing is bringing real-time video and data to the warfighter,” Uhm continues. “In the JTRS Cluster 1 modem architecture, FPGAs account for the majority of the value of the signal-processing chain.

Xilinx officials are addressing key issues for the JTRS community, most notably the cost and power consumption of software-defined radio modems, Uhm says.

“Xilinx has unique enabling technology that can significantly lower cost and power consumption in the modem, perhaps even resulting in savings of greater than 50 percent, especially for high-­channel-density radios like those required for AMF,” Uhm says. “Essentially, Xilinx commercial-off-the-shelf FPGAs can be used as SCA-enabled System-On-Chips (SoCs) supporting shared resources.”

Xilinx demonstrated the technology at MILCOM in Monterey, Calif., last month “with great response,” Uhm says.

Uhm says there are two aspects to the Xilinx solution.

First, a partial reconfiguration of Xilinx FPGAs enables the radio to share resources as the SCA runs a waveform within a specific portion of the FPGA. While this waveform operates, one or more waveforms run in other portions of the FPGA while maintaining the first waveform. “This is in contrast to dedicated resources where only one waveform can be supported on a set of processing devices,” Uhm says. “For multichannel radios, this can result in a major reduction in processing resources, thereby lowering cost and power.”

Second, the Xilinx Virtex-II Pro and Virtex 4 FX FPGAs have embedded hard 405 PowerPC processors that enable them to function as true system-on-chips, Uhm explains. Xilinx partner ISR Technologies runs the Green Hills INTEGRITY real-time operating system, CORBA, and the SCA Core Framework on the embedded 405. “Previously, a discrete general-purpose processor was necessary in the radio to run all this infrastructure,” Uhm says.

SDR market

Researchers at Venture Development Corp. in Framingham, Mass., say the U.S. military is nearly creating the SDR market all by itself.

VDC experts estimate the military market for SDR software will total between $2.5 million and $3.5 million between 2003 and 2007. Military software spending will peak in 2004 because of JTRS cluster ramp-ups, but decrease overtime as work shifts from research and development to production, they say.

“The military has successfully demonstrated SDR’s abilities and will continue to push this technology to its limits,” VDC analysts say. “Meanwhile, commercial wireless products have slowly evolved toward SDR architectures. New device and architectural design advances are opening up a wealth of opportunities in existing and new wireless markets.”

The global market for merchant embedded computer boards in military and commercial communications will be about $1.4 billion. SDR hardware platforms represent a very small portion of this market today, but should grow to more than 11 percent of the market by 2007. “Military applications currently dominate this market, but the mix is expected to shift to commercial applications as these markets emerge,” VDC experts say.

“These recent contracts will help to further entrench traditional military players like General Dynamics, Lockheed Martin, and Northrop Grumman,” says Senior VDC Telecom/Datacom Analyst Chad Hart. “However, these recent awards will also help catapult several smaller SDR vendors’ revenues such as PrismTech and Vanu as well as create many new opportunities for many other emerging players outside of the contract teams.”

The JTRS program has four sub­programs, know as clusters. Contracts for Cluster 5 and the AMF cluster are awarded. Initial contract awards, primary contractors, and subcontractors for the four clusters are:

Cluster 1-initial award $857 million

Prime contractor: Boeing

Subcontractors: Agile Communi­cations, Nova Engineering, BAE Systems, BBN Technologies, Harris RF, Northrop Grumman, Rockwell Collins, Vanu, ViaSat, Xetron

Cluster 2-Update of existing contract

Prime contractor:Thales

Subcontractors: Innovative Concepts

AMF CLUSTER-(previously Clusters 3 and 4)

Team 1 Prime contractor: Boeing (initial award $54.6 million)

Subcontractors: BBN Technologies, Harris Corp., L-3 Communications, Northrop Grumman Space Technology, MILCOM Systems Corp., Rockwell Collins

Team 2 Prime contractor: Lockheed Martin (initial award $51 million)

Subcontractors: BAE Systems, Cisco Systems, General Dynamics C4 Systems, NOVA Engineering, Raytheon Integrated Communications Systems, Scientific Research Corp., Thales

Cluster 5-initial award $295 million

Prime contractor: General Dynamics

Subcontractors: Agile Communica­tions, Altera, BAE Systems, Motorola, PrismTech, RedZone Technologies, Rockwell Collins, Thales, Vanu

Harris to participate in AMF Joint Tactical Radio System program

Officials at Harris Corp. in Rochester, N.Y., won a 15-month pre-system development and demonstration contract for the U.S. Department of Defense (DOD) Airborne, Maritime/ Fixed-Station Joint Tactical Radio System program (AMF JTRS). The Boeing-led team was one of two teams awarded a development contract. The second phase of the AMF program is to be awarded by the end of next year.

The AMF program merges airborne and maritime/fixed station communications requirements into one combined-acquisition approach, Harris officials say. Once operational, AMF radios will be go into more than 150 aircraft, ships, and land stations, enabling them to communicate seamlessly and efficiently.

“This program win expands our role in maritime systems to be a full-spectrum communications system supplier,” says Chet Massari, president of the Harris RF Communications division. “This also strengthens our relationship with the U.S. Air Force Electronic Systems Command,” which Harris also supported with their AN/PRC-117F(C) radios.”

Harris RF Communications division is leading the system security architecture and integration of the maritime radio system, and is one of two radio developers and manufacturers for the Boeing team. Harris Government Communications Systems division in Melbourne, Fla., is providing systems support for the program.

Harris develops software-defined radios, JTRS-compatible hardware, Software Communications Architecture (SCA) compliance, waveforms, and programmable cryptology solutions. The company is a supplier to the U.S. Navy of advanced high-­frequency (HF) communications systems, and was recently selected to develop SCA-compliant Advanced-EHF (Extremely High Frequency) Communications Systems.

Boeing chooses Mercury for the JTRS Cluster 1 testing program

Officials at Boeing in Seattle selected equipment from Mercury Computer Systems in Chelmsford, Mass., for the Joint Tactical Radio System Cluster 1 testing program.

The ADV-3000T tuner solution, developed by Mercury Computer Systems, is used in the Wideband Networking Waveform (WNW) test suite for the JTRS Cluster 1 Program. The tuners are based on the 6U CompactPCI (cPCI) form factor and provide a high-speed and low-noise RF downconverter by leveraging a digital synthesizer architecture.
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Boeing engineers will use Mercury-developed software radio tuners, exciters (transmitters), and synthesizers for their WNW (Wideband Networking Waveform) test suite for the program.

“The Mercury tuners achieve the high level of performance necessary for testing this broad-based application under varying test conditions,” says Deborah Wilson, head of the Network Technologies group in Boeing’s Network Communications Systems organization. “The configuration provides a reliable solution that enables interoperability and operational effectiveness among the diverse platforms in the military spectrum.”

The JTRS Program is a U.S. Department of Defense initiative designed to provide voice, data, and video communications between U.S. and allied warfighters through software- programmable radio technology.

The tuners were developed at Mercury’s RF Center of Excellence, which was formed following the acquisition of Advanced Radio Corporation earlier this year, and are based on the 6U CompactPCI form factor.

“Mercury’s advanced digital synthesizer technology provides an integrated RF solution that enables extremely fast tuning speeds combined with ultra low noise performance,” claims Barry Isenstein, vice president and general manager, Defense Electronics group at Mercury. “Both performance characteristics are critical to the development of the WNW test suite.”

Thales Shares in Joint Tactical Radio System Cluster 5 program win

Officials at Thales Communications Inc. in Clarksburg, Md., announced that the company is a core member of the General Dynamics Joint Tactical Radio System (JTRS) Cluster 5 team, which has been awarded a $295 million contract by the U.S. Army to develop small, light­weight software-defined radios for use by all branches of the U.S. Armed Forces.

The Cluster 5 effort will provide joint U.S. forces with three different communication device types - manpack, handheld, and small form factor for embedded applications. JTRS consists of software-programmable and hardware-configurable digital radio equipment that provides flexibility and adaptability to support joint service requirements, meeting future warfighting needs for decades to come. As many as 14 applications or form factors will be specified under the contract, each driven by an advanced radio core the size of a credit card.

Thales has experience in small-form-factor radios for battlefield use. The Thales AN/PRC-148, a multiband, multi­mode SDR (known as the Multiband Inter/Intra Team radio or MBITR) is used in Afghanistan and Iraq. Thales is also developing the JTRS Cluster 2 handheld radio, which recently completed a successful early operational assessment.

All of the Thales Cluster 5 development and manufacturing work will be at the company’s headquarters in Clarksburg. A new Software Development Center opened on the Clarksburg campus to support continued expansion and to accommodate anticipated growth associated with this award.

“Our role on Cluster 5, combined with our Cluster 2 Program, has positioned the company to be the key provider of JTRS technology for small and battery- powered applications for the foreseeable future,” says Mitch Herbets, president and chief executive officer of Thales Communications

In addition to Thales Communications the General Dynamics core team includes BAE Systems of Wayne, N.J., and Rockwell Collins of Cedar Rapids, Iowa. The General Dynamics team is also supported by subcontractors Motorola in Schaumberg, Ill., Vanu in Cambridge, Mass., Agile Communications in Rancho Cucamonga, Calif., Altera in San Jose, Calif., Datasoft in Tempe, Ariz., Sarnoff Corp. in Arlington, Va., Tessera in San Jose, Calif., General Dynamics Robotic Systems in Westminster, Md., General Dynamics Advanced Information Systems in Arlington, Va., and RedZone Robotics in Pittsburgh, Pa.

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ICS develops ruggedized software radio mezzanine

Engineers at Interactive Circuits and Systems (ICS) Ltd. and its parent company Radstone Group in Towcester, England, have developed the PMC571, a rugged, commercial-off-the-shelf single-channel software radio mezzanine card.

The PMC571 offers wide bandwidth analog-to-digital and digital-to-analog conversion capabilities at software radio frequencies, ICS officials say. Combining it with Radstone’s PowerPC and DSP (digital signal processing) capabilities will enable customers to create multi-function blade products offering analog to digital and digital to analog conversion, field programmable gate array (FPGA), DSP, and processing in a one-slot configuration.

“We have exposed the PMC571 to numerous potential customers and, based on their very positive feedback, we have decided to launch the product here at the SDR Forum,” says Ken Armitage, vice president, product development at ICS. “The PMC571 leverages ICS’s leadership in data acquisition and software defined radio and Radstone’s expertise in ruggedization.”

At the heart of the PMC571 is a four million gate FPGA that provides the platform for application-specific software development within a Xilinx Virtex II environment. Its 64-bit/66 MHz PCI interface ensures compatibility with the latest generation of Radstone Quad PowerPC Signal Processor boards in addition to VMEbus PowerPC and CompactPCI single board computers, ICS officials say. The PMC571 is available across all of Radstone’s five ruggedization levels.

The device is backed by Radstone’s “Whole Program Life COTS.” These services include application and technical support; repair; and “product lifecycle management,” which gives customers control over the issues associated with component obsolescence and over configuration management, Radstone officials claim.

The Radstone Group acquired ICS in 2003. More information can be found at

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