A new technological problem in 0.1�im resolution airborne SAR(synthetic aperture radar) motion compensation design procedure was discussed. High azimuth resolution means large synthetic aperture length and wide integration angle, thereby echo data collected in stripmap mode might include remarkable residual motion errors related with azimuth angle between the radar and the target. The impact of platform aperture-dependent motion errors in stripmap mode on airborne SAR image quality was analyzed. It shows that the errors cause geometry distortion and azimuth defocusing. Based on the relation between radar instantaneous illuminate time and Doppler frequency, an aperture-dependent motion compensation approach was put forward to improve image quality. This method applies segmentation and compensation data in azimuth direction and enters into the processing scheme integrated with conventional motion compensation,the first order motion compensation and the second order motion compensation. Simulation results validate the whole analysis and the proposed procedure.
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