孔径扩展的一种改进算法

A modified method of extended towed array algorithm

针对扩展拖曳阵尺寸算法进行阵列扩展中存在的重叠阵元位置约束问题,提出了一种基于扩展拖曳阵尺寸算法的改进阵列扩展算法。该算法通过在测量间隔内增加快拍获取时域信息,再将重叠相关器提供的孔径域相位信息平均化处理,获得相位修正因子补偿拖线阵连续测量的相位差,实现孔径扩展。该方法能够在未知源的先验信息和连续测量中阵元的空间位置不重叠情况下实现孔径扩展。仿真和实验结果表明,该方法能有效扩展阵列孔径,准确估计信号到达角。针对较低信噪比信号,该方法能够获得比扩展拖曳阵尺寸算法更好的相位估计和方位分辨性能。

A modified array extension method based on extended towed array measurements method is proposed to overcome restriction on the positions of the overlapped hydrophones.In this paper,towed array is extended by using more snapshots and compensating phase differences obtained by aperture domain averaging of phase differences from an overlap correlator.So phase correction factors in the proposed method can be estimated without restriction on the positions of the overlapped hydrophones and information of the target.Results of simulation and experiment show that the proposed method can improve ability of estimation.This method achieved better angular resolution than extended towed array measurements method in signal with low signal-noise-ratio condition.