LFM脉冲雷达回波Doppler与多径时延的联合估计

Joint Estimation of Doppler and Multipath Time Delay of Overlapping Echoes for LFM Pulse Radar

基于最大似然参数估计 ,本文提出了一种对LFM脉冲雷达回波Doppler频移和多径时延联合估计的方法 .该方法先利用WHT估计Doppler频移 ,然后结合发射信号的先验知识重构参考信号 ,最后利用WVD能将时间上有重叠的多径信号在时频域分开的特性 ,采用本文称之为“修正时频相关函数”估计多径时延 .该方法只需一个周期的脉冲信号就能完成频移和时延的联合估计 ,对加性高斯白噪声具有强的鲁棒性 ,其运算量小 .

A new method for estimating the Doppler and multipath time delay of the overlapping echoes for LFM pulse radar by only one period pulse signal is presented. First, the Doppler frequency is estimated by Wigner-Hough transform. Then, a reference signal is reconstructed using the prior knowledge of the transmitted signal and the frequency parameters. Finally, using the property that Wigner-Ville distribution can separate each echo from overlapping echoes in time-frequency plane, the multipath time delay is obtained by a so-called the modified time-frequency correlation function proposed in this paper. The proposed method is characterized by the stronger robustness of additive Gaussian noise and the lower computational cost.