一种适用于浅海小信噪比条件的声源目标定位技术

文章将匹配场处理技术引入一种新的目标运动分析方法——长时间积分法中，用根据实际海洋传播条件计算所得的声场作为拷贝场向量，替代传统方法中所采用的平面波模型。由于充分利用了声场的空间结构，使得该方法不仅能够完成传统目标运动分析中定出目标方位的功能，而且还可以定出其距离和深度。同时，因积分时间的增加还大大提高了对目标的检测性能。该方法可用于解决小信噪比条件下，声源目标的检测和定位问题。尤其适用于浅海、在声信号的传播因受波导和多途现象影响而严重偏离平面波的情况。仿真结果表明：采用平面波模型时，在信噪比低于-28dB时，声源目标参数就已相当模糊；而当采用匹配场处理技术，在信噪比降为-33dB时，仍可精确地得到声源目标的参数。

A technique of source target localization for low SNR case in shallow water

This paper combines matched-field processing with a novel method of target motion analysis, i. e. , long-time integration approach. The acoustic field calculated on the basis of real ocean propagation conditions is used to produce the modeled vector instead of using the plane wave model. This method can not only estimate the source target in bearing that can be accomplished by the conventional target motion analysis, but also the source range and depth because it fully utilizes the unique spatial structure of the acoustic field. Moreover, because of the increment of integration time, it improves the detection performance substantially. This method can be used to handle source target detection and localization in low SNR cases. Simulated results indicate that when a plane wave model is adopted, the estimated source target parameters are very ambiguous with a SNR of - 28dB. However, if the matched-field processing technique is adopted, the source target parameters can be precisely estimated even when the SNR is as low as - 33dB.