Near-Field 3d Sar Interpretation Based on Lidar and Sar Calibration

The near-field array three-dimensional SAR can obtain the three-dimensional electromagnetic scattering characteristics of targets and present the imaging results in the form of point cloud. In recent years, it has been gradually used in the field of target RCS measurement. However, there are some problems in near-field array three-dimensional SAR images, such as interference, sidelobe and missing of target shape. Lidar has the characteristics of high positioning accuracy and strong target shape description. The fusion of Lidar with the near-field array three-dimensional SAR can effectively assist the scattering characteristic diagnosis of SAR images, in which the calibration plays an important role. This paper presents a calibration method for Lidar and near-field array three-dimensional SAR. The method is divided into three steps of calibration target design, extraction and alignment. By designing a special calibration target, correcting the imaging position deviation of Lidar, and converting the problem of calibration corresponding point selection into a problem of matching target set, the coordinate system of Lidar and SAR can be aligned. The effectiveness of the proposed method is verified by the experimental results of measured data.