Research on the Array Gain of Vertical Array of Vector Hydrophone in Deep Sea

The vector hydrophone can simultaneously measure the sound pressure and particle vibration velocity in the sound field, and its dipole directivity can overcome the ambiguity of port and starboard. In the isotropic noise field, the vector hydrophone can obtain a combined gain of 3-4.8dB. In general, vector hydrophones are often applied in the form of an array, which is ideal deep-sea acoustic equipment. Array gain describes the improvement of output signal-to-noise ratio (SNR) of an array compared with the input SNR of a single element, which reflects the sonar target detection performance to some extent. In this paper, we make full use of the multi-channel output of the vector hydrophone vertical array (VHVA). Combined with the sound pressure-vibration velocity joint processing technology, we discuss the additional gain for different vector combinations. The trial results of a 16-element VHVA in the South China Sea validate that the array gain of VHVA can be significantly increased by 2-3dB compared with the traditional sound pressure hydrophone vertical array. The research results in this paper provide a new idea for improving the target detection performance for VHVA.