Chirp Scaling Algorithm Integrated with COAA to Improve Airborne SAR Image Quality

Chirp Scaling Algorithm (CSA) is integrated with Contrast Optimization Autofocus Algorithm (COAA) via properly modifying azimuth processing of CS to incorporate COAA in it, resulting in improving airborne SAR image quality. RCMC is precisely corrected by means of CSA without interpolation, on the other hand, precise estimation and correction for the second phase error in SAR raw data is accomplished. To improve the phase error estimation precision and speed, modified iteration step is used, resulting in more effective application of COAA. In this paper, the SAR processing flow diagram of the two integrated algorithms is given. Finally, the effective experimental results are shown with real stripmap broadside SAR data.