基于DSP的漂移扫描CCD星图快速识别

为了提高漂移扫描CCD的识别速度,实现同步 卫星实时定轨,提出基于数字信号处理器(DSP,digital signal processor)的星图快速识 别算法。在嵌入式DSP数据处理 平台上优化传统的三角形识别算法,采用二次匹配识别算法,即分区间筛选子星表中参考星 参与初匹配,利用初匹配结果推算CCD底片模型,根据背景恒星与子星表参考星的对应关 系将所有恒星进行二次匹配。对分辨率为1528×1528实拍星图的实验处理结果表明,由于引 入了DSP与改进了识别算法,在很大程度上加快了漂移扫描CCD星图识别速度,所耗时间 仅为传统星图识别算法的50%,且识别成功率达到98.4%。

Fast identification of star images from drift-scan CCD based on DSP

to improve identification speed of star images which are taken by drif t-scan CCD and realize real-time orbit determination of synchronous satellite,a fast star ima ge identification algorithm based on DSP is proposed.The big data is calculated on the platform o f embedded DSP, on this basis,the twice match method which is an optimized triangle identificat ion method is proposed to accelerate the calculation speed.The main steps of the new method a re that selecting reference stars from the star catalogue as the form of interval to as the first matching reference stars,then calculating the CCD negative model based on first matching outcomes, the CCD negative model represents the relationship between background stars and referenc e stars in catalog, in the end,matching all stars based on the CCD negative model.The experiment r esults of star images whose resolution is 1528×1528show that because of introducing DSP and improving identification method,the identification speed is become faster in a great part .The processing time taken by new method is only 50% than that of traditional triangle identifica tion algorithm. Meanwhile the identification rate is up to 98.4%.The outcomes of the experience s validate the advantages of the new method on aspect of real time capability an d identification rate.