Research On The Effects Of Platform Motion Error Of Tdi Image Quality

Line-scan image sensor uses a one-dimension pixel array to capture2D image in a scanning method. Image quality is limited by illumination and speed of movement. TDI (Time Delay and Integration) image sensor is an advanced type of line-scan image sensor which uses a2D pixel array to delay and accumulate the signal derived from every single scanning line. The signal-to-noise and sensitivity can be improved without sacrificing spatial resolution and speed. This is useful when it comes to critical situation where illumination level is extremely low or where the relative speed of movement is very fast. In recent years, the development trend of the space optical remote sensor on earth observation has proved that TDI CCD image sensor based on the technology of scanning has large field of view and high resolution imaging potential. It has abroad application in high speed and low light level field. TDI CCD becomes the main approach of the remote sensor lightened and the development of the optical remote sensor on earth observation.Because of the complexity of the imaging system, TDI CCD operation is a complicate project with high risk and precision. So adequately research is needed before put into application. But experiment in real environment is very difficult and expensive. Imaging simulation technology can research on and optimize the technical indicators satellite to ensure the performance of the TDI CCD camera in space imaging, satisfy technical indexes of satellite with the best balance to achieve advancement and engineering cost.This paper mainly studies on imaging simulation modeling of TDI CCD camera system, research the influence of the attitude parameters on imaging quality by setting the parameters for image simulation, and evaluating the image. Ideal imaging model is established with combination of internal structure and working principle of TDI CCD. The TDI dynamic integration, random noise and the platform motion error are also added to establish the imaging simulation model. Platform motion error includes linear motion, attitude angles and attitude angular velocities. Attitude angles include the yaw angle, roll angle and pitch angle. The speed of yaw angle, roll angle and pitch angle belong to attitude angular velocities. Analyze the results of quality of images that are simulated by the imaging simulation model with different TDI CCD integration number and various parameters, and then study the influence of different factors on the quality of TDI CCD imaging.