On making the current military radios cognitive without hardware or firmware modifications

Cognitive Radio (CR) using Dynamic Spectrum Access (DSA) provides the military radios, an ability to operate in un-predictable interference environments. CRs are capable of sensing their environment and autonomously changing the radio parameters such as frequency, bandwidth and power, to avoid interference. Large amount of resources have been invested by the Department of Defense (DoD) on building these radio systems which are currently not DSA enabled. This paper provides a way to make current military radios DSA capable without making any hardware or firmware modifications to them. Radios are made DSA capable by using an external sensor as compared to an embedded sensor containing advanced feature based sensing algorithms, application level messaging and a cognitive engine, which is written in a high level language that resides outside the radios. A real-time over-the-air demonstration for such a cognitive radio test-bed using a network of three Warfighter Information Network - Tactical (WIN-T) Local Area Waveform (LAW) nodes in friendly and un-friendly interference was carried out at the Ft. Dix facility of US Army CERDEC. This paper provides a brief overview of the system, operation of this test-bed and some field demonstration results.