Passive target classification based on the sound field coherence characteristic

Passive target classification is a crucial issue in underwater acoustic signal process domain. This paper starts from the difference of sound field caused by surface target and underwater target, a method of passive target classification based on the sound field coherence characteristic is proposed. According to the theory of normal mode, the mechanism of the interference pattern of sound field is expatiated, and the acoustic field coherence characteristics which can distinguish the surface target and underwater target are extracted, the numerical simulation of the proposed method is carried out, the result shows that, by filtering the normal mode and extracting the sound field coherence characteristic to discriminate the surface target and underwater target is valid.