Robust Ultra High Frequency (UHF) Satellite Communications Protocol for UUVs

"A robust data communications protocol is proposed to improve UHF SATCOM in UUV applications. Harsh sea states, power constraints, and antenna-size limitations contribute to degraded performance and must be mitigated to provide reliable communications insupport of long endurance UUV missions. This program combines an innovative new data-link protocol with error-correction coding and adapts it to non-Rayleigh fading to provide robust communications with UUVs under such adverse conditions. The proposedprotocol was originally developed for use in next-generation, over-the-horizon, terrestrial radio systems, which must tolerate severe bi-directional fading, and has been validated in US Army field trials. The link protocol is optimized to provideextremely low error rates, while minimizing link management overhead and overall data latency. In Phase I, a channel model based on FLTSATCOM and UFO specifications, expected sea states, UUV antenna characteristics, and selected SATCOM modems will bedeveloped. The protocol will be optimized for the data rates and channel conditions planned for UUV applications. Simulations will be performed to validate the recommended protocol implementation, and a preliminary working protocol specification will bedeveloped. Plans will be developed for prototype implementation and testing over a simulated or live satellite link in Phase II. The proposed data-link control protocol can be used in both existing