Motion Parameter Estimation and Focusing From SAR Images Based on Sparse Reconstruction

This letter presents a new motion parameter estimation method using synthetic aperture radar (SAR) images based on sparse reconstruction. The method uses orthogonal matching pursuit, which correlates a SAR image with elements in a reference basis. The reconstruction result provides a high-resolution focused image and corresponding motion parameters. It does not require narrow-beamwidth assumption and prior motion information, as compared with the existing method based on matching pursuit. We design the reference basis by theoretically analyzing the performance degradation due to parameter mismatch. We further calculate required position and velocity parameter resolutions in the basis. The calculated resolutions are validated by means of simulations. Imaging examples with real SAR images of a scene acquired over Ottawa, Canada, show the effectiveness of our method.