Mobile underwater acoustic communication based on hyperbolic frequency modulation signal.

With the rapid development of mobile platforms such as that of the autonomous underwater vehicle (AUV) applied in various areas such as marine information acquisition, and subsea networking, an urgent need exists for robust communication for AUV-state-monitoring, AUV real-time control, and other areas of development. We expect to establish a robust mobile underwater acoustic communication system and are particularly concerned with severe Doppler effect and multipath propagation. The hyperbolic frequency modulated (HFM) signal is used to estimate Doppler scale and achieve timing synchronization. As for the multipath propagation effect, HFM spread-spectrum modulation (HFM-SS) improves communication performance. An experiment of mobile communication was conducted in a lake, and the lake experiment has demonstrated the effectiveness of the HFM strategy, in which AUV played a role as a mobile node.