Estimation and Characteristics of Low-Frequency Ambient Sea Noise from Far-Field Ships

To study the rapid estimation method and characteristics of low-frequency ambient sea noise generated by far-field ships, firstly, based on the reciprocity principle of sound fields and the fact that the number of noise sources significantly exceeds the number of receiving array elements, the positions of noise sources and receiving array elements were swapped to effectively reduce the sound field estimates and the running time. Secondly, a vertical directionality analysis method for ambient noise generated by ship noise was derived. And lastly, the ambient sea noise generated by ship noise in the Philippine Sea was estimated and analyzed, and the validity of the estimation method was verified based on measured data in the region. The estimation method presented in this paper can be used to predict the level and directionality of ambient noise generated by ship noise in a large area of sea, and acts as technical support for the meaningful use of sonar arrays in the actual marine environment.