Three-dimensional Trajectory Reconstruction Method of Moving Targets Using Multi-channel Airborne WasSAR Based on L-Shaped Antenna

The airborne wide-angle staring synthetic aperture radar with the ground moving target indication (WasSAR-GMTI) can observe moving targets from multiple angles over extended periods. However, existing airborne WasSAR-GMTI methods exhibit the low accuracy and poor robustness in the three-dimensional (3D) trajectory reconstruction of moving targets. To address these issues, this paper has proposed a 3D trajectory reconstruction method of moving targets using the multi-channel airborne WasSAR based on the L -shaped antenna. The L -shaped antenna system consists of the along-track antenna and cross-track antenna subsystems. First, for the along-track subsystem, the clutter suppression interferometry (CSI) algorithm is applied to detect moving targets, which can extract motion parameters, mainly including the slant range, doppler center and along-track interferometric phase. These parameters are used to estimate the position of the moving target on the equivalent reference plane. Then, for the cross-track subsystem, the cross-track interferometric processing is applied to extract the cross-track phase at the same reference position. Finally, the slant range, doppler center, and cross-track phase are combined to estimate the 3D position of moving targets and then reconstruct their 3D motion trajectory. The proposed method is validated using both simulated and real WasSAR-GMTI data, and experimental results demonstrate that the proposed method has the good performance in the 3D trajectory reconstruction of moving targets.