观测平台转向时稀疏贝叶斯学习方位估计
Sparse Bayesian learning for direction-of-arrival estimation with a turning observation platform
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摘要: 针对观测平台转向时固定安装于其上的声呐线列阵指向快速变化导致的空间谱谱峰变宽问题,提出一种稀疏贝叶斯学习方位估计方法。该方法利用大地坐标系下不同接收快拍中的空域稀疏信号具有相同先验分布的特性,将转向过程中多个阵列指向分别对应的接收快拍信息联合处理,以求得目标方位。仿真分析与海试数据处理显示出,所提方法可以获得谱峰较尖锐的空间谱,具有较高的测向精度和角度分辨力,此外,对由左右舷模糊引起的伪峰有较强的抑制效果。所得结果表明,所提方法可以有效解决谱峰变宽问题,提升了平台转向时的方位估计性能,同时有效地利用阵列指向的变化提高了线阵抗左右舷模糊能力。Abstract: When the observation platform turns,the changes of the array orientations will cause spatial spectral peak broadening.To resolve this problem,a Sparse Bayesian Learning(SBL) method is proposed to estimate the source Direction-Of-Arrivals(DOAs).Considering that the spatial-domain sparse signals from different snapshots in geodetic coordinates have the same prior distribution,the proposed method combines multiple received snapshots corresponding to different array orientations in the SBL framework for DOA estimation.Simulation analysis and sea trials data processing show that the proposed method can obtain sharper spatial spectral peaks,and is superior to the existing methods in estimation precision and angle resolution.Besides,it suppresses the fake peaks caused by the left/right ambiguity more effectively.The results indicate that the proposed method can effectively solve the problem of spectral peak broadening,enhanced the DOA estimation performance during the turn,and improve the anti-left/right ambiguity ability by utilizing the changes of the array orientations.