基于空时导向约束的天基雷达离散旁瓣杂波判别方法

由于天基雷达覆盖范围广，大量强离散杂波(小型岛礁、陆地铁塔等)会从天线旁瓣进入雷达系统，其多普勒特征与目标相同，极易造成虚警。针对以上问题，该文提出基于空时导向约束的天基雷达离散旁瓣杂波判别方法，该方法首先选取空时自适应处理(STAP)杂波抑制后检测到的潜在“目标”(包含真实目标与离散旁瓣杂波)距离多普勒单元及其附近单元；然后根据杂波多普勒频率与空间角度的耦合关系获得各杂波单元对应的空时导向矢量；最后利用获得新的导向矢量构成的滤波器再次对“目标”距离多普勒单元及其附近单元进行滤波处理，此时真实目标信杂噪比会大幅度降低，而离散旁瓣杂波信杂噪比变化不大，从而实现离散旁瓣杂波的判别。理论分析及机载实测数据处理证明该方法具有良好的稳健性和可靠性。

A Discrete Side-lobe Clutter Recognition Method Using Space-time Steering Vectors for Space Based Radar System

On account of the large coverage of space based radar, a lot of discrete strong side-lobe clutter, which shares familiar Doppler feature with the real moving targets, can be received by the radar system and hence results in false alarms. For this problem, a discrete side-lobe clutter recognition method using space-time steering vectors for space based radar system is proposed. In this method, the “Suspected targets”, including both the real moving targets and discrete side-lobe clutter, are detected after suppressing clutter by employing the Space-Time Adaptive Processing (STAP). The range-Doppler cells where “suspected targets” located in or around are selected. Afterwards, the space time steering vectors of them are obtained based on the coupling relationship between Doppler frequencies and space angles of clutter. Lastly, the above range-Doppler cells are processed again by the adaptive processing filters which are derived from the new space-time steering vectors. Obviously, the signal-clutter-noise ratio of real moving target will be reduced significantly, while it will not change much for the discrete side-lobe clutter. Therefore, the discrete side-lobe clutter can be identified by using the proposed method. Theoretical analyses and multi-channel airborne radar experiments demonstrate the effectiveness and stability of this method.