Airborne Sparse Array SAR 3-D Imaging Based on MURA and Array Deformation Error Compensation

Inhalt:
The cross-track array antenna in airborne 3-D SAR generally exists deformation error, and the deformation slowly changes along azimuth (along-track) direction. Therefore, an compensation for array deformation error and a 3-D imaging method based on MURA, interferometry and Compressed Sensing are proposed. SAR echo is modulated by positive and negative MURA, respectively, to generate two 3-D images. After the performance of interferometry between the two 3-D images, the SAR signal has a sparse representation in frequency domain and the phase error caused by array deformation is removed. We therefore use Compressed Sensing in frequency domain to restore SAR spectrum. By transforming the SAR spectrum from frequency domain to spatial space, the 3-D image of target scenario is reconstructed with array deformation error compensated equivalently. Simulation results demonstrate that the proposed method obtains focused 3-D image of high quality, which reduces the accuracy requirements of array deformation measurement system.