Compressed sensing-based time-varying channel estimation in UWA-OFDM networks

Underwater acoustic (UWA) channels are often characterized as time-varying systems which result in intercarrier interference (ICI) in the reception of orthogonal frequency division multiplexing (OFDM) signals. Recently, compressed sensing (CS) has gained a fast-growing interest by exploiting the sparse nature of UWA channels in OFDM communication networks. This paper studies selected characterizations of the UWA channels, and reviews several mathematical UWA channel models in the literature. Moreover, we present a CS-based sparse channel estimation based on a recently-established statistical channel model, which incorporates acoustic signal propagation laws and random local displacements. The sparse coefficients can be estimated using CS-based reconstruction algorithms.