Reconstruction and Evaluation of Ship Radiated Noise Signal in Ocean Channel

Ship radiated noise can generally be regarded as a random process that undergoes steady states, but the complexity of its generation mechanism makes its spectral characteristics different from white noise signals. Realistic simulation of the time domain signal of ship radiated noise can improve performance of acoustic equipment. In this paper, the analysis methods of the ship's radiation noise line spectrum and continuous spectrum characteristics are studied. The near-field radiation noise data of a certain type of ship under the same operating conditions is analyzed in the time-frequency domain, and the statistically significant radiation noise spectrum characteristics are obtained. The probability density function is used to generate random numbers that meet this statistical characteristic to describe the frequency spectrum of underwater radiating sound sources at various frequencies, and the Fourier synthesis method is used to reconstruct the time-domain pass characteristic of the ship's radiated noise signal under arbitrary sound velocity conditions in shallow water. Finally, the evaluation method of the radiated noise signal modeling results is studied, and the reconstructed signal is evaluated by the similarity calculation between the measured and simulated signal. The results show that the reconstructed time domain signal has higher fidelity.