机载MIMO雷达广义最大似然检测器

Generalized Likelihood Ratio Detector for Airborne MIMO Radars

该文针对机载MIMO雷达在未知统计特性的杂波中目标检测问题,首先给出广义最大似然(GLRT)检测器(MIMO-GLRT),利用MIMO雷达的空间分集特性提高检测性能,并推导出检测概率和虚警概率表达式。然后,基于MIMO雷达杂波协方差矩阵的块对角特性,给出一种简化MIMO-GLRT检测器,大大减小算法的复杂度,同时降低对参考单元数目的要求,并在只有两个接收雷达单元的情形下,推导出简化GLRT检测性能的表达式。结果表明,上述两种检测器相对于杂波协方差矩阵都具有恒虚警特性,能够在未知杂波背景下有效地检测目标。

This paper studies the problem of signal detection in clutter with unknown statistical properties for the airborne MIMO radars. Firstly, a Generalized Likelihood Ratio Test Detector （GLRTD） is proposed to improve the detection performance exploiting the spatial diversity of MIMO radar, and the theoretical expression is derived for the detection performance. Secondly, a simplified GLRTD is derived based on the block diagonal property of clutter covariance matrix to reduce both the computational complexity and the secondary range cell numbers required for clutter covariance estimation, and a closed form expression of the detection performance is given for the special case of two receiver radar elements. The results show that both proposed detectors have CFAR with respect to the covariance matrix of clutter, and can effectively detect targets in clutter.