针对现有抑制杂波距离模糊的方法存在计算量大、缺少训练样本等问题,提出了一种基于稀疏恢复的距离模糊杂波抑制方法。该方法首先提出了基于正交三角分解预处理共轭梯度法的改进正则化欠定系统局灶解法,对杂波进行稀疏恢复,将在时域上无法区分的雷达杂波回波数据变换到等价的空间频率-多普勒频率域上;然后,根据杂波空时耦合特性设计距离模糊杂波空时滤波器,将模糊杂波消除;最后,利用多帧平均处理的方法估计杂波空时谱分布,计算杂波协方差矩阵。与现有杂波距离模糊抑制方法相比,该方法可以克服杂波距离相关性和距离模糊带来的影响,减少稀疏恢复计算过程中出现的“伪峰”,更加准确地估计待测单元的杂波分布特性。

Aiming at the problems of the existing clutter range ambiguity suppression method, such as large amount of calculation and lack of training samples, a novel range ambiguity clutter suppression method based on sparse recovery is proposed. In order to separate the clutter of test cell and ambiguous cells, an improved regularized focal undetermined system solver with conjugate gradient scheme based on quadrature rectangle decomposition is presented, which is used to transform the received signal into spatial frequency and Doppler frequency domain. Then, a spatial and temporal filter is designed to eliminate the clutter of ambiguous cells based on clutter characteristic. At last, the clutter space-time spectrum of test cell is achieved based on multiple cells average method. Compared with traditional range ambiguity suppression methods, the proposed method can mitigate the disadvantages caused by clutter range dependence and range-ambiguity in the same time. The greatly accurate estimation of clutter space-time spectrum in high-resolution can be get. The theoretical analysis and experimental simulations demonstrate the validity of the proposed method.

TN959

国家自然科学基金资助项目(61501501,61601502); 陕西省自然科学基金资助项目(2019JM-322)