基于子孔径图像的低频SAR多通道均衡方法

Low Frequency SAR Multi-channel Equalization Method Based on Subaperture Image

利用多通道SAR系统进行运动目标指示时,通道间的幅相失配严重影响了运动目标检测以及参数估计的性能。针对多通道低频SAR/GMTI系统,提出了一种基于子孔径SAR图像的多通道均衡方法。该方法利用相同视角的多通道子孔径图像,估计该角度对应的幅相误差,在达到较高幅相误差估计精度的同时,也能适应误差随视角的变化。基于车载低频多通道SAR/GMTI实测数据的实验结果表明:该方法能有效地补偿不同通道之间的幅相误差,提高运动目标的检测和参数估计性能。

When the multi-channel SAR system is used for moving target indication,the imbalance in amplitude and phase among channels severely affects the performance of moving target detection and parameter estimation. For multi-channel low frequency SAR/GMTI system,a multi-channel equalization method based on subaperture image was proposed. The method makes use of multi-channel subaperutre images with the same view-angle,and estimates the amplitude and phase errors related to this view-angle at the same time. It can estimates the amplitude and phase errors accurately and adapts to the errors changing with the view-angle. The experiment based on vehicle-borne low frequency multi-channel SAR/GMTI real data demonstrates that this method can effectively compensate for the amplitude and phase errors among different channels and improve the performance of moving target detection.