Key techniques for virtual imaging model construction and correction of rotating imaging satellite

Abstract

According to different scenarios and needs, the rotating imaging optical satellite designs three task observation modes such as wide-area coverage, encrypted observation and regional video, the long edge of the camera field of view is placed radially along the turntable, the short edge of the field of view is placed tangentially, the camera pendulum axis is placed along the short side of the field of view, the pendulum mirror can be adjusted in three gears, the satellite adopts nadir pointing, that is, the rotation axis of the turntable is in the direction of the nadiel, the turntable maintains a normal working speed of 24 ° / s, rotates every 15s, and adjusts one gear per rotation of the camera pendulum mirror. After rotating 3 times in 50s, it can cover the range of 5~60° in the direction of nadir direction. The image obtained based on the above mode has rotation misalignment, different angles, abnormal speed imaging, integration time jump, and internal distortion in a single frame image. Therefore, how to perform sensor correction for multi-angle rotating images to achieve continuous, complete and distortion-free restoration is a key scientific problem to be solved in this paper. The purpose of optical satellite sensor correction is to design the imaging payload and imaging mode, realize seamless image stitching, eliminate image distortion caused by lens distortion, CCD distortion, integrated time jump, allospeed imaging and tremor disturbance, and finally obtain continuous, complete and distortion-free high-quality images. In order to obtain high-quality ultra-large wide format optical satellite images without distortion and seamless stitching, the construction and correction method of virtual imaging model for rotating area array mode is studied, and key technologies such as multi-gear virtual large area array CCD design and construction and virtual correction method based on ideal composite motion model are broken through to achieve distortion-free, seamless stitching and highquality restoration compensation, providing comprehensive, accurate and rapid data and information support for subsequent on-orbit remote sensing applications.