Subsea Broadband Reverberation Modeling and Simulation of High-speed Motion Sonar

Abstract

Subsea reverberation is the main source of interference when torpedoes detect targets in shallow waters where the sound velocity approximately satisfies the negative gradient distribution. In order to obtain the reverberation signal accurately, conveniently and reproducibly, and study its statistical characteristics, this paper proposes a high-speed motion sonar subsea broadband reverberation simulation method based on the Bellhop model. In this method, the seabed area that contributes to the reverberation is divided into several non-uniform scattering units, and the scattering characteristic function of each unit is calculated. The propagation loss is calculated by the Bellhop model. Subsea reverberation analog signal with main influencing factors such as doppler shift. Finally, the time-frequency domain analysis and similarity comparison between the simulated signal and the actual flight signal are carried out. The results show that using the dot product ratio of the probability density distribution of the instantaneous value of the simulated signal and the measured data as the evaluation standard, the similarity between the method in this paper and the actual flight data is greatly improved, which verifies the validity of the model.

Keywords

• torpedo
• subsea reverberation
• motion platform
• bellhop model
• element scattering model