机载雷达超低空多径目标稳健STAP方法

Robust STAP method for supper-low-attitude target detection with airborne radar

超低空目标与环境之间存在耦合多径效应,产生"镜像"虚假目标,严重恶化协方差矩阵估计和运动目标检测性能。针对这一问题,该文提出基于时域优化的多点联合幅相约束的稳健空时自适应处理(space-time adaptive processing,STAP)方法。基于超低空目标及其"镜像"目标多普勒扩展特性的分析,提出了目标及临近空时二维域多点联合幅相约束的STAP方法,并基于保形约束推导了时域响应的解析解,实现了STAP二维响应的主瓣保形,克服了目标多径效应造成的检测性能损失。仿真实验验证了该文方法的有效性。

When a moving target flies at a very low attitude, referred to as supper-low-attitude target, it re-sults in target detection performance loss or target tracking error. This is due to the secondary interaction be-tween the moving and environment clutter , which causes an image of the moving target under the ground/sea. To deal with this problem, a robust space-time adaptive processing （STAP） method based on the optimized joint magnitude and phase constraints in the temporal domain is proposed. The Doppler spread characteristics caused by the supper-low-attitude target and its false image counterpart are analysed. With joint magnitude and phase constraints imposed on and around the target, the mainlobe is well maintained and the performance loss due to Doppler spread is avoided. Simulation examples demonstrate that the robustness and detection performance is significantly improved with the proposed method.