Research on Target Depth Attribute Determination Method Based on Pressure Cross Spectrum in Shallow Water

Aiming at the requirements for determining the depth attributes of submerged targets in shallow water, a novel target depth attribute determination algorithm using dual vertical receiving sensors has been proposed in this paper. This algorithm solves the problems that the existing algorithms generally have the disadvantages of large array aperture, limited sea depth range and limited target type range. In this paper, the theoretical research and experimental analysis of pressure cross spectrum excited by target have been carried out. The receiving depth selection method suitable for different sea conditions and the method for determining depth attributes of submerged targets whose frequencies can excite first three modes have been proposed. Secondly, the impact of waveguide parameters on algorithm performance has been analyzed, in order to verify the feasibility and robustness of the algorithm. Then, according to the performance analysis results of the algorithm, the specific applicable conditions and usage methods of the algorithm have been given. The experimental results show that when the receiving sensors are placed near the ideal receiving depths, the new proposed algorithm is suitable for the case where the line spectrum frequency can excite first three modes and for low signal-to-noise ratio conditions, but becomes more sensitive to the sound speed profile. It is only suitable for weak negative gradient conditions. The critical depth value is larger than ideal value, and it is difficult to adjust.