近距离慢速目标检测杂波抑制方法

Clutter Suppression Method for Short Range Slow Moving Target Detection

针对强杂波环境下近距慢速运动目标检测问题,该文提出一种基于相位编码及子空间投影的杂波抑制方法。主要对周期探测信号调制Chirp相位编码,通过回波慢时间维解码使杂波近似白化,降低杂波与目标回波相关性,再依据白化后杂波及有用信号成分自相关性差异分离出信号和杂波干扰子空间;最后将接收信号投影至正交于杂波子空间的信号子空间来抑制杂波。由于该方法中杂波空间的构建不需要假设杂波模型,避免了模型假设与实际环境不匹配的问题。仿真结果和实测数据处理结果证明该方法在低信杂比条件下性能明显优于传统方法。

This paper proposes a method of clutter suppression based on phase encoding and subspace projection for close slow-moving target detection in strong clutter environment. In the framework, the periodic detection signal is modulated with phase encoding, and the clutter is whitened through echo decoding of the slow-time dimension to reduce the correlation between clutter and target echo. Furthermore interference subspace is constructed on the basis of the autocorrelation differences between whitened clutter and useful signal components. The receiving signal is projected to the signal subspace orthogonal to the clutter subspace for clutter suppression. Since the construction of clutter space does not need to assume the clutter model, it avoids the problem of mismatch between the model hypothesis and the actual environment. Simulation results and real data processing results show that this method has better performance than conventional methods under low signal-to-clutter ratio.