信息密度评价采样成像系统的合理性分析  

Rationality Analysis on the Information Density Evaluation for Sampled Imaging System

作　　者：贺金平[1] 阮宁娟[1] 刘兆军[1] 刘雨晨 庄绪霞[1] 

机构地区：[1]北京空间机电研究所,北京100094

出　　处：《航天返回与遥感》2016年第3期100-110,共11页Spacecraft Recovery & Remote Sensing

基　　金：国家重点基础研究发展计划项目(973项目)(613210)

摘　　要：针对信息密度评价采样成像系统性能理论依据不足的问题,文章提出通过对不同成像系统的信息密度和所成图像的质量评价参量进行一致性分析,来研究信息密度评价采样成像系统性能的合理性。信息密度是融合了系统调制传递函数、信噪比和混叠的综合成像质量表征参量,文章对成像系统的信息密度计算式进行了推导,在此基础上介绍了计算信息密度所需各分量的数学模型,进而对仿真流程进行了描述。仿真实验结果表明,成像系统信息密度值随着成像系统设计参量数值的变大而不断增加,计算得到的图像质量评价参量也呈现了相同的规律,信息密度与图像质量评价参量之间保持了较好的单调一致性。调整成像系统参数进行物理验证实验,实验结果进一步证明了利用信息密度评价采样成像系统性能的合理性。Considering the deficiency in the theoretical basis about information density evaluating sampled imaging system, this article proposes a method that compares the information density calculated from the different system parameters with the corresponding images＇ assessments in order to obtain the rationality analysis on the information density evaluation for sampled imaging system. Information density contains system MTF, SNR and aliasing, and is a comprehensive imaging representation. Firstly, the calculation formula of information density is derived. The useful representation models for calculating the information density are introduced. Then the simulation procedure is described. Experimental results show that under certain conditions, the higher the system designed parameter λF/P is, the higher the information density of imaging system is. And the quality assessments of the corresponding images also become higher. The information density keeps good monotonicity with image quality assessments. Physical verification experiment is implemented through adjusting the system parameters. Experimental results further prove the rationality of using information density to assess the sampled imaging system.

关 键 词：信息密度 混叠失真 系统评价 成像质量表征 图像熵 航天遥感 

分 类 号：O438[机械工程—光学工程]