空间太阳望远镜星载CCD图像压缩单元的研究  

Compression Technique for onboard CCD Image of Space Solar Telescope

作　　者：贾志宏[1] 耿立红[1] 孙才红[1] 金声震[1] 

机构地区：[1]中国科学院国家天文台空间天文技术实验室

出　　处：《光电子．激光》2007年第3期285-288,313,共5页Journal of Optoelectronics·Laser

基　　金：国家"863"计划资助项目(863-2.5.2.25)

摘　　要：针对空间太阳望远镜(SST)卫星上海量的观测数据和在轨存储、下传能力有限的矛盾要求在轨压缩科学数据,本文在分析SST星载CCD图像压缩需求基础上,根据空间环境的限制和国内的设计研制能力,采用基于小波变换(DWT)和稀疏矩阵压缩的压缩算法,设计了星载压缩单元(DCU),并在DSP加FPGA结构的硬件平台上进行算法仿真和系统联试。测试结果表明,DCU可以在6s内对2048×1024pixels的太阳图像进行大于5倍压缩,压缩信噪比(SNR)优于26dB,均满足SST图像压缩需求。DCU实现了星载图像处理系统的国产化设计,已通过验收。In the space solar telescope（SST） mission,because of the conflict of large volume of observation data and limited resources for store and transmission,the onboard data compression is needed. According to the requrements of data processing and the ability of native development,we adopt an in-line compression scheme. In this paper,the algorithm based on the wavelet transform is given and optimized on the hardware platform using DSP and FPCA. Data compression unit（DCU） can compress the solar images into 1/5 of original data and the processing time is less than 6 seconds,and the SNR is greater than 26 dB which satisfies the SST images requrements. DCU realizes the implement of native SDPU,which has passed the examination.

关 键 词：CCD 图像压缩 小波变换 DSP 

分 类 号：V447[航空宇航科学与技术—飞行器设计]