Space-Variant Motion Compensation in Ultra-high Resolution Airborne Spotlight SAR
超高分辨率机载聚束SAR空变运动误差校正

The compensation for space-variant motion errors is one of the main issues in ultra-high resolution airborne SAR imaging. This paper first discusses the characteristics of space-variant motion errors of airborne spotlight SAR, and deduces the quantificational relationship between space-variant motion errors and SAR imaging parameters such as scan angle, size of illuminated scene and grazing angle. Then, it presents a comprehensive processing scheme for motion compensation of high resolution airborne spotlight SAR, which is based on the sub-patches processing and a new method of range resample using chirp disturbance. This scheme can make up for the deficiency of traditional process and deals well with severe space-variant motion errors in ultra-high resolution imaging. Finally, computer simulations prove the validity of the scheme.