COMPENSATION OF THE ATTITUDE INSTABILITY EFFECT ON THE IMAGING PAYLOAD PERFORMANCE WITH OPTICAL CORRELATORS

摘要

This paper addresses the problem of image corrections for satellite pushbroom cameras due to satellite attitude instability effects. Satellite cameras with linear sensors are particularly sensitive to attitude errors, which cause considerable image distortions. A method of distortions correction is presented, which is based on the real-time recording of the image motion in the focal plane of the satellite camera. The proposed concept uses in-situ measurements of the image motion with additional CCD-sensors in the focal plane and real-time image processing of these measurements by an onboard joint transform optical correlator. The proof of feasibility of the concept and detailed performance figures have been derived with a hardware model of the optical processor, developed and manufactured under ESA-contract. The paper presents a description of the concept and key technological elements, as well as test results at component and system (end-to-end image restoration) level and closes with a specification of a full scale onboard system.