基于分数阶Fourier域滤波的SAR多运动目标检测和参数估计

SAR多运动目标的检测和参数估计较单运动目标的难度大大增加,传统的WVD方法在处理多分量线性 调频信号时存在交叉项干扰的问题,改进的WVD-HT方法可减弱交叉项的影响,但并不能从根本上解决交叉项问题, 同时计算量也很大。文中提出一种基于分数阶Fourier域滤波的多运动目标检测和参数估计方法,在运动目标和静止目 标信号分离后通过逐个消去强目标信号,有效地解决了弱目标信号的检测和参数估计问题,由于分数阶Fourier变换是 线性变换,从而免除了交叉项的困扰。仿真和实测数据的处理结果验证了算法的有效性。

SAR Multiple Moving Targets Detection and Parameter Estimation Based on Filtering in Fractional Fourier Domain

It becomes very difficult for SAR to detect and estimate the parameters of the moving targets when there are multiple moving targets. The cross - interference problem arises when the conventional WVD method is used to process multiple LFM signals. The improved WVD - HT method can be used to mitigate the impaction of the cross term but cannot solve this problem radically and at the same time its computation load is heavy. Based on filtering in Fractional Fourier Domain, a method to detect and estimate the parameters of the multiple moving targets is presented in this paper. The target detection and parameter estimation problem from weak signal is solved effectively by eliminating the strong target signal one by one after separating the moving targets signal from the clutter. It is not disturbed by the cross-term problem because the Fractional Fourier transform is a linear transformation. The simulation and the processing results of real radar data prove the effectiveness of this method.