Military radios give generals the jitters

The Defense Department’s $6.8 billion Joint Tactical Radio System (JTRS, pronounced jitters) is in serious trouble. Mainly because it doesn’t work.

The problem to be solved is a serious one: the military has way too many radios, on way too many different frequencies, and they’re too big. The bright idea solution? Build a radio that talks to anything on any frequency.

Essentially, the JTRS program is aiming for something that’s almost physically impossible, or at least extremely expensive, experts say. . . .

The problems are legion. The desire to use a single antenna for many different wavelengths bumps up against laws of physics, which make it difficult to pull in strong signals across the spectrum. An amplifier that works across the whole spectrum will use much more electrical power than one tuned for a specific frequency band. Waveforms and transmissions that are speedily handled by analog systems, such as the widely used Link-16, are much tougher to achieve with digital computation. And the challenges go on. . . .

[Maj. Gen. Michael] Mazzucchi [who commands the Army’s Communications-Electronics Lifecycle Management Command] said that the military has learned a lot over the past few years and is now much smarter about the technical challenges involved in fielding a radio designed to provide seamless network connectivity. For example, initially, every JTRS box has to host all the waveforms and all the software for the network. To do so requires high-performance computer processors, which translates into more heat and power.

But for the JTRS radio to be carried on missiles to provide guidance and on other platforms such as unattended ground sensors, there is no requirement for all that processing power.

“So maybe one size does not fit all,” Mazzucchi said. “Maybe we can have it run just one wave form, then you wouldn’t have the same battery, heat and processing speed challenges.” — Defense News

Defense Tech has more on how military radios might interconnect — more intelligently — in the future, as well as an analysis of how the failure of JTRS to break the laws of physics puts the Army’s Future Combat Systems in jeopardy.