GAO: JTRS software lacks portability

The Government Accountability Office has criticized one of the major underlying tenets of the Defense Department’s Joint Tactical Radio System program: low-cost portability of software among the planned family of JTRS radios.

The GAO report also highlights problems the program faces with network interoperability and the ability to obtain enough frequency spectrums for the radios.

DOD planned to use JTRS to develop a wide range of radios whose functions would be defined in software waveforms rather than hardware. Those waveforms –- which define frequency, modulation, message format and transmission system -– could then be used with a wide range of platforms at a lower cost than developing and purchasing separate hardware radios, which operate in specific frequency bands such as VHF or UHF and with specific modulation -- AM or FM, for example.

But in a report released last week, GAO said that when a JTRS waveform is developed, “the software code is designed to operate on a particular radio’s hardware architecture. When the same waveform is transported to different hardware, changes to the software code may be necessary to ensure proper integration of the waveform onto the new hardware. The more costly the integration effort is, the less portable the waveform.”

Although the JTRS software communications architecture specifies design rules to enhance portability across hardware platforms, “the limited experience of porting waveforms this far has shown significantly higher costs and longer schedules than anticipated,” GAO said.

Because the JTRS waveforms are unable to support network interoperability, the GAO report states, the Joint Program Executive Office (JPEO) for JTRS at the Space and Naval Warfare Systems Command plans to initially meet interoperability requirements through the use of network gateways.

The JPEO is uncertain whether it will use an existing radio to support the gateway function or use a separate piece of hardware, which could add to the size and weight of some platforms, GAO said.

Lack of a fully functioning gateway could impede battlefield communications, the report states. For example, it could mean that a ground combatant using a radio built on the Soldier Radio Waveform could not call directly for fire support from an aircraft using the Joint Airborne Networking-Tactical Edge, GAO said.

The JPEO expects to begin gateway development in 2007 and is assessing whether to fold this into an upcoming system development contract or a separate vehicle, the JPEO said.

JTRS radios will require considerable spectrum for effective operations, especially when using new networking waveforms that operate in several different bands. Obtaining sufficient spectrum is problematic because the program must compete with civilian and other military spectrum users, the GAO report states.

JPEO is working through the DOD spectrum certification process to resolve issues, but “certification of software-designed radios remains a challenge, [because] these processes were designed around hardware-based radios and may not fully support the certification of cutting-edge technologies such as JTRS,” the GAO report states.

GAO endorsed management changes in the JTRS program, particularly the establishment of JPEO, but said the office still faces management challenges, including developing formal acquisition strategies and a test and evaluation plan.