高分辨雷达扩展目标检测算法研究

Research on extended target detection for high resolution radar

针对高分辨雷达扩展目标检测问题,本文建立了高分辨雷达回波模型,推导了在目标信息完全已知的理想条件下的最优检测器形式,给出了检测算法的性能上界.讨论了广义似然比检验在目标信息不同程度缺失情况下的检测器形式,给出了可实现检测器的检测性能上界.基于广义似然比检验,提出了一种基于散射点个数估计的双门限检测器.仿真表明该方法检测性能优于现有检测方法.

The problem of extended target detection for high resolution radar is addressed. After modeling the radar echo signal, the optimal detector in the ideal case, in which all information of the target is known, is derived. The performance of the optimal detector, which gives an upper bound of the detection performance for all potential detectors, is analyzed. Then the GLRT detector is discussed in five cases in which the information of the target is partially or entirely unknown. The detection performances of these detectors are analyzed, and the theoretical and simulation results confirm that the more information about the target a detector has, the better detection performance it shows. The order of the detection performance of these detectors reveals that the detection performance of the order accumulation detector gives an upper bound of the detection performance for all practical detector for which all the information of the target is completely unknown. A double threshold detector based on scatter number and GLRT（BS-GLRT） is proposed. In the proposed detector, the number of target scatters is estimated by comparing signal amplitudes at all range cells against the first threshold, and all the amplitudes above the first threshold are accumulated and compared against the second threshold to make detection decision. Simulation confirms that the proposed detector outperforms the existing methods in all cases and the detector performance is very close to the upper bound.