Underwater Acoustic Single-Carrier Communication Systems with Frequency—Domain Equalization System Based on Sparsity-Adaptive Orthogonal Matching Tracking Algorithm Channel Estimation

In this study, a low-complexity sparsity adaptive orthogonal matching tracking algorithm (SAOMP) is proposed for the single-carrier communication system with frequency-domain equalization (SC-FDE). The OMP algorithm can attain high estimation accuracy with low estimation cost, but it necessitates a priori channel sparsity information as a stopping condition, which, in practical applications, is often unknown. In this study, for the characteristics of the SC-FDE, returning after detecting a small amplitude of multipath is used as the stopping condition of OMP, which reduces the probability of pseudo-multipath being estimated under the influence of noise. Both numerical simulations and experimental results of maritime hydroacoustic communications reveal that the SAOMP algorithm is a suitable channel estimation algorithm for SC-FDEs.