Modeling of High Background Noise in large area Ocean Based on Measured Data

摘要

Noise level is an important parameter to determine the detection threshold of underwater acoustic equipment in sonar equations, how to increase the background noise level effectively in the ocean is a hot issue in underwater acoustic research. This paper presents a modeling method for oceanic high background noise based on measured data. Firstly, using the probability density function of a large number of samples of measured marine environmental noise, a random signal with energy at each frequency satisfies a certain probability distribution is generated. Then, the sound propagation theory is used to calculate acoustic transmission loss over a specified distance when the parameters of the ocean channel are known. Based on the predetermined increased value of the background noise level, the sound source level of the interference source is given, at the same time, the amount of amplification of interference source relative to the measured background noise is determined. Finally, several underwater distributed acoustic transducers are used to emit these broadband interference signals; thus, the purpose of increasing the noise level in a large area ocean is achieved. The results show that our model maintains its own spectral characteristics of the marine environment and ensures that the interference sound source can't be exposed easily. The research ideas in this paper provide references for semi-physical simulation under different signal-to-noise ratios under lab.