基于信道传播理论的多基地远程海底混响研究

Propagation theory for bi-static long-range bottom reverberation in shallow water waveguide

针对浅海多基地远程海底混响,以声传播的线性信道近似理论为基础,通过确定海底界面的不均匀起伏特性,对入射声波的远距离异地混响脉冲响应函数进行求解.对非水平分层介质的浅海波导,利用绝热简正波求解信道的传输函数,得出了小角度斜坡海底的远程海底混响强度,以下坡海底为例,分析对比了不同海底倾角斜坡海底对远程异地混响强度及其衰减规律的影响.理论仿真表明,波导的传输效应对多基地远程海底混响强度的影响不可忽略.

Bi-static long-range bottom reverberation in shallow water is investigated, and the impulse response function is derived using the linear theory of sound channel. For the case of almost layered medium, the adiabatic mode solution is introduced for the derivation of transfer function. The reverberation intensity is calculated for the range-dependent waveguide, and then both the intensities and the decaying rules are compared with their corresponding counterparts in different wedged sea areas. It is shown that the propagation effect on intensity of distant bottom reverberation can not be neglected for the hi-static active sonar in shallow water waveguide.