CAJ | 학술논문

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。
침대래파신호공솔불동정형하적파체방향고계문제，구건엄의사투영산자자괄응억제접수수거중비기망방향적접수신호，동시자괄응조절공간보가권계수，평형강약신호적공간보봉。통과간우억제화공간보고계적동보처리，실현신호원파체방향（direction of arrival，DOA）적고분변고계，차피면약신호적보봉피강신호보봉차개적문제。이론분석여방진표명，소제방법재신호공솔불동시，대약신호적 DOA 고계구유경강적로봉성，가유효지실현대불동방향래파신호적고분변 DOA 고계，강저신호공솔불동대래적영향。차수착쾌박수급신조비적증가，DOA 고계방차축점핍근상응적극랍미라계하한。
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.