Simulation technique of radiated noise from underwater target and its implement of simulator

The simulation of radiated noise from underwater targets, including surface ships, submarines, high speed gunboats, cargo and fishing vessels, is the key technique of testing passive sonar system and acoustical decoy. In this paper, a proper model which could best and simply describe the typical features of the realistic radiated noise is presented. As to the sources, the radiated noise is composed of the machinery induced noise, propeller induced noise and hydrodynamic noise. In the frequency domain, the spectrum of radiated noise is composed of continuous power spectrum and line spectrum. Thus, according to the frequency-domain dynamic feature of the noise with continuous spectrum and line spectrum, the radiated noise is modeled and simulated, which can best describe the signature of underwater noise sources. And the radiated simulator based on DSP hardware systems is proposed. By signal processing to the output of the simulator with the power spectrum, the results show that the simulator can reconstitute typical acoustic signatures of the radiated noise.