Maneuvering imaging quality of space TDI push scan optical remote sensor

The imaging quality of TDI push broom camera in maneuvering imaging mode is analyzed from the perspectives of resolution and radiance. Firstly, the Los tracking method is proposed to analyze and calculate the resolution of TDI and linear array directions. By constructing the coordinate conversion matrix between sidesway and satellite points, the unit vectors of TDI and linear array in different maneuver angles are obtained. Then, the projection vectors of the unit vectors in two directions on the ground are calculated along the Los direction, the ground pixel resolution is calculated, combined with the parameters of the camera, the orbital height and the earth radius. At the same time, the integration time of different fields of view are obtained according to the projection rate of the satellite on the ground, and the MTF degradation of edge fields of view under different TDI stages is analyzed with the reference integration time of central field of view. Taking a remote sensing model as an example, the specific analysis and calculation are carried out, and the requirements for the yaw angle are put forward according to the degradation of MTF. The calculated results show that the MTF of the edge spectrum section has decreased to 0 when the TDI series is 60 under the large side sway, so the TDI stage should be selected carefully in orbit. Then, combined with the theoretical calculation and on orbit image, the influence of the atmosphere on the image contrast under different side or yaw angles is analyzed. The analysis shows that the yaw will change the atmospheric transmission path, thus affecting the target contrast. The analysis results can provide a reference for the later image correction.