合成孔径声纳中拖体偏航角的估计方法分析

Estimation algorithm for yaw of tow-body in synthetic aperture sonar

单发射阵多接收阵合成孔径声纳成像中,拖体的偏航角是主要的运动误差之一,为得到高质量的成像结果必须对其准确估计并补偿。主要分析了偏航角的两种估计方法,即偏置相位中心算法和基于相邻两帧图像互相关算法。通过仿真和湖试试验结果表明,在强点目标场景下偏置相位中心算法估计偏航角的精度较低,且随拖体的速度的增加估计精度大幅度下降,当拖体速度过快导致无重叠相位中心时该算法失效,而基于相邻两帧图像互相关算法估计的偏航角相对于偏置相位中心算法不仅精度高,且具有很好的鲁棒性。

Yaw of tow-body is one of primary motion errors in synthetic aperture sonar with single transmitter and multiple-receiver configuration,and in order to get high quality reconstructed image the yaw must be accurately estimated and compensated.Yaw estimation based on Displaced Phase-Center（DPC） algorithm and cross-correlation algorithm of the adjacent reconstructed ping images are discussed in detail.Simulation and lake experiment results with the scene of prominent points confirm that the estimation accuracy of yaw using DPC algorithm is poor,and that the accuracy would be worse along with the velocity of tow-body being increased,and the DPC algorithm is even invalid when there is no overlapped phase center.Estimation of yaw based on the cross-correlation algorithm of the adjacent reconstructed ping images is more accurate and robust than that of using DPC algorithm.