Survey of Narrow Band Vocoder Technology.

The USAF has a need to identify a vocoder to insert into a Low Probability of Intercept LPI communications system. It should be small, lightweight, low power, capable of operating in many types of aircraft, and capable of processing intelligible, natural sounding speech at 400 to 600 bitsseconds. Two separate units are needed one to be used in a near-term brassboard test system and one to be used in a far-term production system. Weighted characteristic values are combined through a mapping and summing procedure to form a Figure of Merit for each system. Using these characteristic values, primary vocoder candidates have been identified and are discussed in this paper. Additional keywords Waveforms, Theses, State of the art, Brassboard models, Multimode, LASARSLPI Antijam Secure Airborne Radio System. Author