Research On Astronomical CCD Image Processing Technology Based On DSP

Astronomical CCD (Charge-Coupled Device) image is affected by kinds of noises, it is necessary to research how to reduce noises effectively and to realize the detection for fixed stars and moving space targets. Due to the massive data quantity, the real-time realization of algorithms is also the problem to be solved.In this paper, the principle of an astronomical CCD image processing system based on DSP and its key technique in software and hardware are systematically introduced. This system can work in two modes: fixed star detection mode and moving space target tracking mode.For fixed star detection mode, four background estimation algorithms are analyzed and compared, a simplified and effective background estimation algorithm (two point background estimation) is proposed. Object extraction is realized through connective areas distinguishing, this paper also proposes a method for exact background estimation to improve the precision of centering and magnitude determination.For the moving target tracking mode, this paper propor.es a fusion target detection algorithm to realize the detection for weak object. Considering the character of satellites' moving in the eyeshot of telescope, a real time target tracking method is presented. To realize the real-time system, an IPC plus signal processing board structure are used, and FPGA+DSP structure is adopted in extended signal processing board. Further more a reasonable cooperation of the whole system also makes the system resource fully utilized.