Simulation of Dynamic Ship Radiated Noise Signal

The total intensity and the spectral distribution of ship’s radiated noise signal changes dynamically as the ship navigates. Conventional static simulation methods are focused on exhibiting non-changing or fixed patterns of signal’s characteristics. For applications that require high-fidelity models, methods that can correctly simulate the above mentioned dynamic characteristics are preferred. In this paper, such a method is proposed and investigated. It is an enhancement of the static simulation method. Firstly, the resulting statically simulated intermediate signals are taken and divided into segments in the time domain. Secondly, for each segment and each frequency point of signal’s linear and continuous spectrum, the intensities are adjusted according to the acoustic transmission loss formula and then merged. Finally, the modulation process is conducted. The simulation experiment results show that the simulated noise signals can exhibit the dynamic characteristics of the navigating ship through the variation on total signal intensity and spectral distribution. Moreover, the simulated signals are also smooth, natural, and non-sectional in auditory sense.