Target Depth Attribute Classification Method with Vertical Linear Array in Shallow-Sea Negative Thermocline Waveguide

Target depth attribute classification is one of the difficult problems in the field of underwater acoustic information. To discriminate the target depth under conditions of shallow-sea negative thermocline waveguides and vertical linear array, this paper analyzes the formation mechanism of the sound field elevation structure and digs into the differences in sound field elevation angle between surface and submerged targets. A target depth attribute classification method is proposed based on the dependence of the sound field elevation angle on the source depth in a thermocline waveguide. This method extracts the sound field elevation angle as a classification feature and sets the modal elevation angle of the critical mode calculated based on normal mode theory as a threshold. The criterion of surface/submerged target is made through binary judgment. Simulation results prove the feasibility and effectiveness of this method.