Simulation of Moving Target Propeller Active Sonar Echo Signal Based on Underwater Acoustic Micro-Doppler Effect

Addressing the challenge of simulating target echo signals for active sonar in deep-sea environments, this paper proposes a method based on the underwater acoustic micro-Doppler effect for simulating propeller echo signals of moving targets. Initially, the BELLHOP ray acoustic model is employed to compute the target signal’s intrinsic ray, amplitude, phase, and delay information, thereby constructing the underwater propagation channel for the simulated sonar signal and adding noise. Subsequently, micro-Doppler feature detection technology from radar is adapted and applied to active sonar echo signal simulation, considering underwater acoustic characteristics. This approach enables micro-Doppler feature modeling of underwater target propellers to capture propeller-specific echo signals. The MATLAB simulation platform generates a Linear Frequency Modulation (LFM) detection signal, which, when transmitted through the underwater acoustic channel, forms an echo signal with micro-Doppler traits. This signal then reaches the hydrophone’s receiving range through the return channel, realizing micro-Doppler characteristic signal simulation for active sonar detection of moving targets. The simulation results indicate that, in deep-sea high-frequency active sonar scenarios, the proposed method significantly enhances the target signal characteristics within the echo signal compared to traditional methods, yielding a simulation closer to real sea trial received signals.