SAR motion compensation based on the correction of residual attitude errors

As residual attitude errors are likely to affect the synthetic aperture radar (SAR) imaging, this paper presents a SAR motion compensation algorithm based on the correction of residual attitude errors. The existing methods all use the antenna stable platform to correct the attitude errors, and then compensate the trajectory deviations in the following imaging process. Besides compensating the trajectory deviations, the modified method of this paper also considers the influence of residual attitude errors on the SAR imaging, and can compensate both the trajectory deviations and the residual attitude errors. Compared with the existing methods, the modified method in this paper can more precisely compensate the imperfect motion on the SAR imaging, especially good for the SAR system with a small platform, near operating distance and a narrow antenna beam. Such a system causes severe residual attitude errors and needs to consider the influence of antenna beam pointing errors on the imaging. The validity of the modified method presented by this paper is demonstrated by the result of the experiment.