针对来波信号功率不同情形下的波达方向估计问题,构建广义斜投影算子自适应抑制接收数据中非期望方向的接收信号,同时自适应调节空间谱加权系数,平衡强弱信号的空间谱峰。通过干扰抑制和空间谱估计的同步处理,实现信号源波达方向(direction of arrival,DOA)的高分辨估计,且避免弱信号的谱峰被强信号谱峰遮盖的问题。理论分析与仿真表明,所提方法在信号功率不同时,对弱信号的 DOA 估计具有更强的鲁棒性,可有效地实现对不同方向来波信号的高分辨 DOA 估计,降低信号功率不同带来的影响。且随着快拍数及信噪比的增加,DOA 估计方差逐渐逼近相应的克拉美罗界下限。
To solve the problem of direction of arrival (DOA)estimation,generalized oblique projection op-erators are constructed to cancellincident signals coming from undesired directions.Since the signals impinging on the array may have different power,one kind of weighting factor is used to balance the height of the spactial spectrum adaptively.Through synchronously suppressing interference and implementing spatial spectrum esti-mation,a high resolution of the source’s DOA parameters is realized and the phenomenon that the peaks of weak signals are covered by strong ones is avoided.Both the theoretical analyses and the numerical simulation experiments indicate that the proposed approach has good robustness against direction finding of signals,espe-cially the weak sources,with distinct power.The bad influences introduced by the signals’power can be over-come by the proposed approach,and a high resolution of signals’DOA parameters can be effectively achieved with different incident angles.What’s more,the standard deviations of the estimated DOAs are asymptotically close to the corresponding Cramer-Rao bound along with the increased snapshots and signal to noise ratio.