Combining sparse recovery approaches with underwater acoustic channel models for robust communications in the shallow water paradigm

Abstract

Shallow water acoustic communication techniques are fundamentally challenged by the rapidly fluctuating multipath effects due to oceanic phenomena such as surface wave focusing, specular reflections from the moving sea surface, Doppler effects due to fluid motion as well as sediment-dependent absorption from the sea bottom. Several signal processing techniques have been recently proposed that specialize in recovering the shallow water acoustic channel components using compressing sampling and mixed norm optimization theory. However, these novel techniques are typically agnostic of underlying underwater acoustic propagation phenomena. Furthermore, state-of-the-art in shallow water channel estimation typically does not account for the three-way uncertainty principles governing the localization of sparsity, time, and frequency for the time-varying shallow water acoustic channel. This talk will focus on recent techniques proposed in this domain, their relative benefits and shortcomings; as well as offer new insights into how we can combine knowledge of basic underwater acoustic propagation physics with state-of-the-art in sparse sensing and related techniques to achieve robust shallow water channel estimation. The talk will also provide an overview of equalization techniques that can be harnessed with channel estimation techniques proposed.