一种新的互耦条件下宽带信号DOA估计算法

基于一致聚焦和Khatri-Rao子空间的思想,提出了一种新的互耦条件下宽带信号DOA 估计算法。首先,通过在阵列两端设置辅助阵元来补偿各个频率处的互耦效应;接着,对补偿后的协方差矩阵进行一致聚焦操作,并重排成一个高维矩阵;最后,通过搜索Khatri鄄Rao 子空间谱估计出宽带信号的DOA。算法适用于互耦未知的场合,对宽带信号频率谱是否平坦没有要求,且在互耦自由度较小时能够分辨多于阵元数的宽带信号。计算机仿真结果证明了算法的有效性。

A Novel DOA Estimation Methed for Wideband Signals in the Presence of Mutual Coupling

Based on the idea of consistent focusing and Khatri-Rao subspace, a new wideband DOA estimation method for wideband signals is proposed in the presence of unknown mutual coupling. Firstly, the effect of mutual coupling at each frequency can be compensated by setting several auxiliary elements on each side of the array. Then, by applying consistent focusing operation on the compensated covariance matrices, a higher dimensional matrix is thus formed by rearranging the focused covariance matrices. Finally, the DOAs of wideband signals can be estimated by searching the Khatri-Rao subspace spectrum. The proposed method can be suitable to the scenario that the mutual coupling is unknown, and does not require that the frequency spectrum of wideband signals is flat. Moreover, it can resolve more signals than the number of array elements when the freedom degree of mutual coupling is small. Simulations results demonstrate the effectiveness of the proposed method.