An Efficient HRWS Sar Reconstruction Method Based on Frequency Domain Back Projection

Azimuth unambiguous reconstruction is a significant and challenging step for HRWS SAR imaging. Compared with conventional frequency-based reconstruction algorithms, the image domain reconstruction (IDR) method can be well applied to curved trajectory SAR and compensate channel amplitude and phase errors adaptively but suffers from huge computational complexity. To improve the efficiency of reconstruction, in this paper, we propose a sub-image reconstruction method based on frequency-domain back-projection (FDBP-SIR) for HRWS SAR imaging. In the proposed method, the frequency domain back-projection method is used to improve the efficiency for each sub-image imaging. Moreover, as the calculation of the index and the partial com-pensation phase are performed once before the sub-image back-projection process, it further improves the computational efficiency. The experimental results show that the proposed method improves the computational efficiency and achieves a high-quality reconstruction same as IDR.