Fast underwater acoustic data link design via multicarrier modulation and higher-order statistics equalization

摘要

There is a global need to develop reliable wireless digital communications; for the underwater environment, with sufficient performance and efficiency to substitute for costly wired systems. Scientific research conducted in the oceans and coastal areas could benefit through the reduction of cost for acquisition and downloading of data from remote monitoring sites. Undersea robotics could benefit through improvement of the communications features of manned and unmanned underwater vehicles for control and for near real-time conveyance of data and images. The theoretical formulation of the underwater acoustic data communications problem includes modeling of the stochastic channel to incorporate a variety of impairments and environmental uncertainties; and proposal of compound strategies for parallel data transmission systems using multicarrier modulation (MCM) in a higher-order statistics (HOS) signal processing domain. An MCM system obtains enhanced usage of available bandwidth, as well as higher transmission rate and error threshold in comparison to the single carrier modulation (SCM) type, and thus establishes a faster communication link which is inherently more immune to impulsive type impairments.