Simulation And Analysis Of The Co-phasing Error Of Segmented Synthetic Aperture System

With the development of ground-based optical telescopes and space telescopes, telescopes develop towards to higher resolution and stronger light-gathering The resolution of the telescope system is related to the size of system aperture, the larger the aperture is, the higher the resolution of the telescope system becomes. Therefore, in order to improve the resolution capability of the system, it is necessary to increase the size of the aperture of the telescope system. However, in practical applications, many factors limit the size of the system aperture, such as materials, processing, cost, loading capacity and so on. The traditional single-aperture optical imaging technology is difficult to achieve large-diameter telescope. The use of optical synthetic aperture imaging technique can increase the size of the telescope system. Currently, most countries use large segmented telescopes, which are composed of a series of small-diameter reflecting mirror. Unlike traditional singleaperture optical systems, the segmented-mirror of large segmented telescopes generates deviation due to the influence of non-alignment, environment and other factors. Therefore, large segmented telescopes produce co-phasing errors, which leading to the image quality of system becoming obscure. In this paper, the principle of large segmented telescopes was discussed in detail, and the error tolerance of system was analyzed.Firstly, the principle of optical synthetic aperture imaging system was analyzed. The principle of the imaging system was analyzed from the perspective of general imaging model, including traditional single-aperture optical systems and synthetic aperture systems. It describes the similarities and differences between synthetic aperture imaging system and conventional optical system. Some typical structures of the pupil are modeled from the physical optics theory, which deriving a point spread function of system. And the simulation of point spread function was analyzed.Secondly, the primary mirror of large segmented telescopes was modeled. Large segmented telescopes use segmented-mirror with hexagon shape. Then, the pupil structure of primary mirror was modeled and deriving a point spread function of large segmented telescopes. For example, the total number of segmented-mirror is given by N = 37, the side length of segments is given by R = 650 mm and the F number is given by F# = 12. The simulation of the ideal system and the effect of primary mirror with gaps were analyzed.Finally, the influence of the co-phasing error on the system was theoretically analyzed and simulated. To ensure the Strehl ratio of the system is more than 0.9, the piston error should be controlled within ?/ 20, the tip/tilt angle of the tip/tilt error should be controlled within ?/ D.In this thesis, segmented synthetic aperture system was theoretical analyzed and simulated for the later engineering applications providing a theoretical basis and technical guidance.