MIMO雷达双向空间平滑的多径目标DOA估计算法

针对多径情况下MIMO雷达低角目标DOA估计问题,提出了一种基于双向空间平滑FBSS的样本复用MIMO雷达低角多径目标DOA估计算法。考虑到MIMO雷达相干信号测角时与多径信号测角时情况的不同,算法采用了MIMO雷达四路径回波信号模型,首先依据MIMO雷达波形分集的特性对接收信号匹配滤波得到虚拟阵列,在此基础上对虚拟阵列采取行列复用并分别进行双向空间平滑,有效提高了低信噪比条件下低角目标DOA估计精度。计算机仿真结果表明,在信噪比小于-12dB条件下,该算法比M-SSMUSIC算法的均方根误差平均减小了1°。

A DOA Estimation Algorithm for Multi-path Target of MIMO Radar Based on FBSS

In the light of low angle target direction of arrival (DOA) estimation problem of MIMO radar under condition of multipath, a DOA estimation algorithm with sample multiplexing at low angle multi-path target of MIMO radar based on FBSS (Forward-Backward with spatial smoothing) is proposed. In consideration of the difference between the coherent signal and multi-path signal DOA estimation of MIMO radar, four path model of MIMO radar echo signal is adopted by algorithm to obtain the virtual array by the matched filter according to the Waveform diversity of MIMO radar, and to reuse the virtual array by rows and columns for FBSS, thus effectively improving the low angle target DOA estimation accuracy on the condition of low signal-to-noise ratio. The simulation results show that the RMSE of the proposed algorithm is reduced by an average of 1 degree compared with the M-SSMUSIC when the SNR less than -12dB.