纯方位目标运动分析的一种“检测前跟踪”技术

A track-before-detect method for bearing-only target motion analysis

被动检测中,当目标信噪比较低时,传统的波束形成估计目标方向有较大的误差,为此我们提出一种改进的检测前跟踪技术,即直接对波束输出的方位-功率图序列做运动分析。对目标所有可能的运动路径进行时间积分,理论上与目标真实轨迹最靠近的路径将获得最大的功率累积量。本文结合纯方位目标运动分析的规律,以不降低检测性能为前提,开发了一种简化的路径搜索策略。在计算机仿真实验中,也证实了该简化搜索策略使得运算量至少降低了两个数量级。

For the passive sonar system, bearing estimates are inaccurate if the signal-to-noise radio （SNR） is very low. This paper presents a new ＂track before detect＂ （TBD） method, which is to integrate Power Bearing Map （PBM） sequence along a hypothesized target track whereas the target bearing sequence needs not be estimated in advance. Intuitively, maximum accumulation appears when the hypothesized track approximates the true target track, because only the true track consistently includes the target during the whole integration time. Furthermore, a simple search strategy among all possible tracks is proposed to reduce the computation load. One simulation example illustrates the performance and efficiency of our TBD method.