Technology doesn’t always evolve smoothly. Never has this been more apparent than with the development of the “next generation” tactical radio for the joint services. With the adoption of the Joint Tactical Radio System (JTRS) radio approach some years back, the use of a software-defined-radio (SDR) architecture seemed like the obvious evolutionary path for tactical, battlefield communications. These radios used digital processing to adapt to new and different waveforms, and communication with other radios, old and new.

While this may have seemed like an obvious evolutionary path, the development of JTRS radios has been plagued by cost overruns. This problem has gotten serious enough to where the Space and Naval Warfare Systems Command (SPAWAR; www.spawar.navy.mil) recently announced its interest in procuring commercial ground radios compatible with JTRS radios—that is, based on the SDR architecture. A special report in the June issue of Microwaves & RF describes several of the commercial-off-the-shelf (COTS) variants of SDR radios that might be used in the place of JTRS radios, at a fraction of the cost. Of course, these are COTS radios that have been developed for “easy” handling, rather than the abuse of the battlefield. They are not designed to weather the temperature extremes or the rough handling of military applications, so any cost savings in procuring COTS versions of a tactical communications radio might be misleading.

JTRS is not one radio, but four different types of radios, including manpack and handheld tactical units. When the JTRS program was restructured in 2005, a Joint Program Executive Office (JPEO) was added so that there might be some coordination in the development of these various different JTRS radios. The fact that there were multiple radios, and also that the technology was being pushed for multiple functions, turned the JTRS program into a complex maze. The ever-rising price of the JTRS radios finally led to the SPAWAR announcement.

The fact that commercial SDR-based radios exist is, at the least, an endorsement of the viability of the technology. SDRs are extremely flexible, secure, can be built in the same form factors as older analog radios, and bring so much more in terms of multimode capabilities. The JTRS program may require managerial updates, but there is no disputing its visionary place in contributing to the advancement of radio technology.