Deep-sea sound-speed profile estimation using two towed temperature-depth sensors

Non-uniform distribution of sound-speed profile (SSP) significantly impacts deep-sea sound propagation. A simple and efficient method is proposed for estimating spatial non-uniform SSP using empirical orthogonal function and towed temperature-depth sensors (TDs). Processing results of a deep-sea experiment show that this method requires only 2 towed TDs, and the root-mean-square error (RMSE) of reconstructed SSP is 1.0377 m/s. Results of the sound-field simulation using different SSPs show the necessity of considering non-uniform distribution of SSP, and the RMSE of transmission loss calculated using the reconstructed SSP is less than 2 dB when source depth is 50–350 m.