四川丹棱机载SAR点目标辐射定标方法

Research on Approach of SAR Radiometric Calibration Using Point Target

作为机载SAR极化合成孔径雷达数据应用必不可少的步骤,SAR辐射定标将图像像素值转化为地物的后向散射系数。利用点目标进行辐射定标的方法具有简单、易于操作的特点且具有一定精度,被人们广泛应用于实际的生产中。三面角反射器稳定性较好且易于操作,并拥有较大的散射截面积,在较宽的角度变化范围内其在雷达系统中的散射截面积变化较小,所以被当成最常用的点目标定标器。本文在阐述点目标辐射定标的基础上,以四川省丹棱县为实验区域,进行基于点目标的辐射定标外定标,得出了该方法具有一定精度且简单实用的特性。

SAR calibration,as a necessary step for SAR data application,makes pixel values related to the backscattering coefficient of ground targets. The trihedral corner reflector,which has high stability,large RCS and little change within a wide angle range,is always used in the SAR calibration. Calibration experiments were carried out,which shows that radiometric calibration using point target is simple,practicable,and relatively accurate.