Warfighter's Needs

JTRS Program Review & Vision Guide


The Warfighter’s Need for Non-Line-of-Sight Communications and Mobile Ad Hoc Networking Drives Development of Ground Mobile Radios

By Barry Rosenberg-Macaulay

FieldsAsk the Army Program Manager for the Joint Tactical Radio System (JTRS) Ground Mobile Radios (GMR) what his program priorities are and he doesn’t hesitate in his response: get JTRS GMR fielded and in the hands of the warfighter as soon as possible.


“The whole purpose of the ground mobile radio system is to fill a capability gap that has been lacking in the field for some time now,” said COL Gregory Fields, Program Manager for JTRS GMR. “The capability gap GMR addresses is the inability of legacy tactical radios to seamlessly pass real-time information throughout the range of military operations.”

Through the Wideband Networking Waveform (WNW), routing and retransmission via the use of mobile ad hoc networking (MANET) capabilities, and multi-channel attributes, JTRS GMR offers a number of unique capabilities that provide the warfighter with an enhanced operational capacity never before realized.

For example, communications in close combat quarters in built-up areas of Iraq hinder signal transmission because of buildings and other obstacles. JTRS GMR has the ability to re-route and re-transmit communications in non-line-of-sight situations to maintain situational awareness on the ground.

“Being able to communicate and share information via the WNW while taking advantage of its MANET capabilities to route critical situational awareness among other non-line-of-sight or signal-diminished combat elements in urban areas or terrain-constrained environments like that found in Iraq or Afghanistan really provides a significant leap in battlefield operations and will truly help save lives,” said Fields.



“The whole purpose of the ground mobile radio system is to fill a capability gap that has been lacking in the field for some time now,” said COL Gregory Fields, JTRS GMR Program Manager.

JTRS GMR is one of five major programs within the Joint Program Executive Office for JTRS. GMR Increment 1 provides the ability to interoperate with legacy radios, as well as providing higher capacity, highly networked communications that are integrated with the Global Information Grid.

It is a four-channel National Security Agency-certified Type 1 and Type 2 software programmable radio that runs WNW and the Soldier Radio Waveform (SRW), as well as software versions of legacy waveforms that include: Single Channel Ground-Air Radio (SINCGARS); Enhanced Position Location Reporting System (EPLRS); Ultra High Frequency (UHF) Satellite Communication (SATCOM); and High Frequency (HF).

JTRS GMR provides dual/simultaneous secure (secret) and non-secure communications on selected channels, or single-mode dedicated Top Secret only communications for all four channels. Although still evolving, the following military vehicle platforms being targeted for use by the GMR system: Abrams battle tank, Bradley Fighting Vehicle, Stryker, Armored Personnel Carrier (M113), M1068, High Mobility Multi-Purpose Wheeled Vehicle, FMTV, MULE and ARV.

“The ability to operate four channels simultaneously eliminates all the legacy hardware systems that are currently out there right now,” said Fields. “Soldiers and marines don’t have to have four or five different radios installed into a HUMVEE or Bradley.  To re-emphasize, it has the capability of being able to conduct secure and non-secure communications simultaneously, or go completely dedicated top secret. No other radio does that. The WNW also gives the radio long range and a networking capability.”

Program Update

JTRS GMR is presently engaged in early Product Qualification Testing (PQT) of the hardware while simultaneously undergoing Formal Qualification Testing of the waveforms. Integration and porting of the waveforms to the hardware and software is an integral part of these developmental testing activities, and necessary in order for them to work in harmony and with full functionality as mandated in the program’s technical specifications. 

“Achieving the desired results in PQT and FQT (Formal Qualification Testing) activities are most critical to progress GMR to the next acquisition phase, which is operational testing,” said Fields.

To ensure that JTRS GMR is fielded as quickly as possible, the program office is working to meet the following milestones:

*Developmental testing that encompasses actual system hardware, including Operating Environment and ported/integrated waveform testing is scheduled for third-quarter 2009 to third-quarter 2010.

*Successful execution of initial operational test events, which are: (1) Limited User Test for FCS-Spin-Out (SO)1 by the third quarter of FY2010 (the program office has delivered 71 pre-Engineering Development Models (EDMs) and 14 EDM radios to support FCS SO 1); (2) Limited User Test for GMR by fourth-quarter FY2010 to first-quarter FY2011

*Achieve Milestone C Approval by second quarter FY11.

*Execute LRIP on schedule to support Multi-Service Operational Test and Evaluation (MOT&E) from third-quarter FY2011 to second-quarter FY2013.

*Conduct a successful MOT&E in the timeframe from fourth-quarter FY2012 to first-quarter FY 2013.

“I want to get this system in the warfighter’s hands as soon as possible,” said Fields. “A lot of folks have been waiting for this for a long time, and we’re really close right now to making our milestones and getting through the PQT, which is a key milestone.

“We expect to have an integrated system of hardware, software and waveforms that is fully functional and which provides a higher capacity throughput than the pre-engineering development models that are being tested now. Those will be followed by a number of limited user tests that will get us ready for Milestone C and authorization for limited production.

“We’re getting much closer to fielding this system. And as I said, it’s badly needed.”

Balancing Schedule, Cost, Risks

Fields only recently took over as the JTRS GMR PM, but he quickly learned what is on the mind of DoD leadership. Because of the desire to field the system as quickly as possible, keeping the schedule on track is, not surprisingly, at the top of the list. 

“Schedule is top priority,” said Fields. “Regarding risks…there are some. When you integrate all the elements of the program, which is something that has never been done before because we’ve never attempted to field a software-defined radio, there is some risk. But I think we have worked through most of the show stoppers.”

Funding is arguably the second bogey of interest, primarily because of concern that lack of funding could hinder the program’s development program.

Said Fields: “I’m going to be looking hard at the technological maturity of the system and making sure we get through these key, developmental test, as well as making sure we have the right amount of funding to do what we need to do within the schedule timeframe.”

JTRS GMR


JTRS GMR, a software defined, multi-channel, multimode communications system, can be reconfigured to emulate and interoperate with current force radios as well as operate new waveforms that have enhanced per-formance capabilities. GMR provides secure communications and enables simultaneous multi-media communications over independent channels to ground vehicle platforms such as: System Integrated Command Post System Carrier, Abrams Tank, Bradley Fighting Vehicle, High Mobility Multipurpose Wheeled Vehicle, Expeditionary Fighting Vehicle, and the Light Armored Vehicle.  GMR will interoperate with force equipment currently used by civilian and military operations.