基于修正空时频分布矩阵的到达角估计

Estimation of direction-of-arrival by using modified spatial time-frequency distribution matrix

讨论了密集信号环境下,雷达侦察系统对信号到达角(DOA)的估计方法。首先对参考阵元的输出作时频分析,估计信号的频率参数,从而选择时频脊点构造方向矩阵;然后对各阵元输出求互Wigner Ville分布(XWVD)以构造修正空间时频分布(STFD)矩阵;最后用修正STFD矩阵代替传统MUSIC算法中的协方差矩阵即可求得信号的时频———MUSIC空间谱,从而得到信号的DOA。计算机仿真结果表明该算法可实现对常规雷达脉冲、线性调频信号等多种信号的DOA估计。

To estimate the direction-of-arrival in a radar reconnaissance system under the multiple-signal circumstance, the method with modified spatial time-frequency distribution matrix is presented. Firstly, the frequency parameters are achieved through time-frequency analysis of the output of the reference sensor. With the frequency parameters, steering matrix is constructed on the point along the time-frequency ridge. Then the modified STFD matrix is constructed with the cross Wigner-Ville distributions of the outputs of the array. By substituting the covariance matrix with the modified STFD matrix, the time-frequency MUSIC spectrum is obtained. The computer simulation results show that the algorithm can be applied to many forms of signals such as pulse and chirp signals.