基于迭代连续匹配追踪的高频地波雷达单次快拍DOA估计方法

高频地波超视距雷达在一个相参积累时间内只能获得空域的单次快拍,在单次快拍条件下进行波达方向估计常常性能很差。针对该问题,本文以压缩感知理论为基础,并根据目标信号在探测方位分布的稀疏性,提出单次快拍下目标方位估计方法。该方法首先利用稀疏变换字典将位于连续方位空间的目标信号变换到满足稀疏条件的离散网格点上;然后采用正交匹配追踪方法获得粗略的方位信息;最后根据迭代最小二乘连续匹配追踪算法得到目标的精确方位。理论分析与仿真证明,该方法可以提高在单次快拍下对低信噪比相干信号的方位估计精度,并且完全适用于阵元数较少的小规模高频地波雷达系统。

Single snapshot DOA estimation algorithm based on iteration continuous basis pursuit for HFSWR

The performance of the direction of arrival (DOA) estimation in high frequency surface ware radar (HFSWR) degrades seriously due to only single snapshot is obtained in one coherent accumulation period. To deal with this problem, a novel DOA estimation method is proposed for single snapshot in angle domain based on compressive sensing (CS) theory and the spatial sparsity of targets. This method firstly transforms continuous targets direction into discrete grid points by sparse transformation dictionary; and then the orthogonal matching pursuit method is used to estimate the DOA roughly; finally, the accurate DOA estimation can be obtained by the iteration least squares continuous basis pursuit algorithm. Theoretical analysis and simulation results demonstrate that the proposed method is effective and much more accurate for coherent signals with low signal to noise ratio (SNR), and another benefit is that similarly high estimation accuracy can be achieved in a small-scale high frequency surface wave radar.