Comparisons of channel estimation for OFDM-based and wavelet-based underwater acoustic communications

In this paper, a wavelet-based underwater acoustic (UWA) communication system is proposed. The convolutional structure of the UWA channel is exploited and the pilot assisted channel estimation is formulated as a sparse recovery problem. Then the restricted isometry property (RIP) of the measurement matrix is investigated via eigenvalue analysis and Gersgorin circle theorem. It´s proved that the sparse recovery of the wavelet-based UWA channel satisfies the RIP. With the above setup, comparisons of channel estimation for OFDM-based and wavelet-based UWA communication systems are deployed. Simulation results show that the wavelet-based system achieves more accurate channel estimation performance than the OFDM-based system under the same conditions of bandwidth, duration, data rate and channel profile.