JTRS and the evolution toward software-defined radio

Various companies have been working on a software-defined radio (SDR) concept for years, pushing the technology envelope to make SDR a reality. From a military perspective, the concept behind SDR has existed for decades with research in military tactical radios culminating in a quest for the USA army's Joint Tactical Radio System (JTRS). Based on open standards, the JTRS program intends to reuse existing system configurations while leveraging evolving technologies to build a family of software programmable and modular communications systems aimed at communications connectivity for warfighters in the digital battlefield environment. This paper provides an overview of SDR by comparing existing and future SDR capabilities with the technical and programmatic challenges faced by the JTRS in its quest to replace static, hardware-intensive legacy radios with a dynamic communications system based on commercially available application software.