Three-dimensional High Resolution Imaging Method of Multi-pass Circular SAR Based on Joint Sparse Model

Multi-pass circular SAR has the capability of three-dimensional imaging, however, under the influence of inadequate sampling of multiple tracks and the changing scattering characteristics with observing angles, the three-dimensional imaging performance of multi-pass circular SAR should be improved to meet the requirements of the interpretation. In this paper, the utilization of the imaging scene sparse distribution in three dimensions including range, azimuth and height is adopted, and the joint sparse reconstruction model is established to achieve high resolution three-dimensional image. Further, for the angle-dependent scattering characteristics of buildings and other man-made objects, adopting non-coherent superposition way for different sub-apertures images to improve the SNR performance of the final three-dimensional image. Imaging experiment of measured data on parking area verifies the validity of this method.