基于激光偏振特性的水下声信号探测方法研究

水下航行体辐射的声波传播到水-空气分界面上时,会在水表面形成微扰,使水表面元产生微倾角.提出一种利用激光偏振特性对水下声信号进行探测的方法,不直接利用散射光强信息,而是利用激光在布儒斯特角附近入射水表面时,反射光偏振特性随入射角剧烈变化的特点对水表面微扰进行高精度探测.建立了该方法的理论模型,得到了入射波、出射波垂直分...

Underwater Acoustic Signal Detecting with the Method of Laser Polarization

The water surface perturbations generated by underwater acoustic signal form submarine ship result in slight change of water surface obliquity.A kind of new method is presented,which can extract underwater acoustic signals by laser polarization characteristic.The used information isn’t scattered light intensity directly,but the tempestuously change of reflected laser polarization state with the angle of incidence when the angle of incidence is near the Brewster angle.This technique is used for precision measure for water surface perturbations generated by underwater acoustic signal.Underwater acoustic signals detection academic model by laser polarization characteristic is built and the relations of P_A(incident light’s power rate of vertical component and parallel component) and P_r(reflected light’s power rate of vertical component and parallel component) with the angle of incidenceθ_i,respectively is analyzed.In particular,the angle of incident lightθ_i can be calculated by measuring P_R directly and the detection of underwater acoustic signal can be achieved if the incident light is natural polarization state.There is no need to measure P_A to this method.The results suggest that the detection based on this technique has higher measure precision and stronger anti-jamming ability.