Combined differential Doppler and time delay compensation for an underwater acoustic communication system

This paper describes a new system architecture for high data rate digital acoustic communication over a shallow underwater channel that is subject to severe Doppler and time delay spread. The method uses high-resolution channel characterization in the time and frequency domains to resolve the main multipath components. This is followed by successive interference cancellation using the Doppler and time delay information for each of the multipaths independently. Directional antennas are not required to spatially filter the multipath components and the simulation results presented are for an omnidirectional receiver. The method works at SNRs as low as 5dB.