第23卷
第7期
2015年7月
文章编号
1004-924X(2015)07-1829-09
光学精密工程
Optics and Precision Engineering
Vol.23No.7
Jul.2015
时间延迟积分CCD空间相机信噪比的影响因素
刘则淘，万志，李宪圣，李葆勇，邵雅荣
（中国科学院长春光学精密机械与物理研究所，吉林长春130033）
源，建立了相机的信噪比模型。分析了辐射亮度、积分级数、行频和系统增益（模拟增益)对信噪比的影响。搭建了实验室辐射定标系统，模拟了相机在轨工作时的辐射亮度条件。通过辐射定标对不同工作参数与相机信噪比的关系进行了
验证。结果表明：对于TDICCD相机来1
的输出信号和信噪比均随着辐射亮度、积分级
定图形噪声在诸多噪声中起主导作用。相机
数和系统增益的增加而增大，随着行频的增加而减小。辐射亮度、积分级
数、行频和系统增益对信噪比的影响量不同。具体来说，即当辐射亮度、积分级数和行频变化量分别为L倍、M倍、倍
时，其导致的信噪比变化量略大于LI/倍、M/倍、r 化幅度随着增益的提高逐渐减小。
关
系统增益只能在相对较小的范围内影响信噪比，且信噪比变
键调：CCD空间相机；信噪比；时间延退积分；辐射亮度；积分级数；行频；系统增益
中图分类号：V447.3；V416.6
文献标识码：A
doi:10.3788/OPE.20152307.1829
Influencefactorson SNRof TDICCDspacecamera LIU Ze-xun', WAN Zhi, LI Xian-sheng, LI Bao-yong, SHAO Ya-rong
(Changchun Institute of Optics,Fine Mechanics and Physics, ChineseAcademyofSciences,Changchun130033,China)*Correspondingauthor，E-mail:Liu_zerun@163.com
Abstract: To quantitatively assess factors affecting the Signal to Ratio(SNR)of a Time Delay Integra tion(TDI)CCD camera, the imaging principle and noise sources of the TDICCD space camera were re-searched and a SNR model was established. The effects of the radiance lightness, integration stages, line transfer frequency and the system gain(analog gain)on the SNR were analyzed. A laboratory radi-ation calibration system was established to simulate the on-orbit radiance conditions of the camera. The relationship between the SNR and different working parameters were verified by radiation calibra-tion. The calibration results show that the photon shot noise, dark current noise and the fixed pattern noise play a major role in all kinds of noise. The output signal and the SNR of the camera increase with the raises of the radiance, integration stages and the system gain and decrease with the raise of the line transfer frequency. The varieties of these factors have different influences on the SNR. Spe cifically, when the variations of the radiance, integration stages and the line transfer frequency are re spectively L times, M times and r times, the variations of the SNR are slightly larger than Li/2 times,
收稿日期：2015-03-20修订日期：2015-04-27，
基金项目：国家863高技术研究发展计划资助项目（No.863-2-5-1-13B）