光学学报, 2012, 32 (2): 0211001, 网络出版: 2011-12-16
基于多光谱遥感成像链模型的系统信噪比分析
System Signal-to-Noise Ratio Analysis Based on Imaging Chain Model in Multispectral Remote Sensing
遥感 多光谱成像 信噪比 成像链 大气辐射传输 remote sensing multispectral imaging signal-to-noise ratio imaging chain atmospheric radiation transfer
摘要
信噪比(SNR)是评价多光谱遥感成像性能的重要指标,在设计多光谱遥感成像仪的最初阶段应进行分析,从而确定各分系统相关参数。多光谱遥感系统的成像链模型综合考虑辐射源、地物光谱反射、大气辐射传输、光学系统成像、分光元件特性、探测器光谱响应和相机噪声等各个环节,可用于进行成像过程端对端的完整分析。以基于滤光片阵列的多光谱遥感系统为例,采用MODTRAN软件进行大气辐射传输计算,对不同太阳天顶角下,不同目标地物计算像面的照度,根据电荷耦合器件探测器的噪声模型,计算出不同工作条件下多光谱遥感系统的SNR。通过对SNR的分析,可给出该类型多光谱遥感系统获得最佳性能的工作条件,并能够结合使用要求进行光学系统参数的优化选择。
Abstract
Signal-to-noise-ratio (SNR) is an important index for evaluating multispectral imaging performance. In the early stage of designing a multispectral imager, SNR analysis should be performed for the determination of subsystem parameters. The imaging chain model of multispectral remote sensing is introduced. Characteristics of radiation source, object spectral reflectance, atmospheric radiation transfer, optical imaging, dispersive element, detector spectral responsivity and camera noise are synthesized to come into an end-to-end analysis. A filter array based multispectral imaging system is modeled. Computation of atmospheric radiation transfer is from MODTRAN under conditions of different solar zenith angles and different surface features. The models of charge coupled device are adopted for characterizing the noise features. SNR for different working conditions are shown for the designed multispectral remote sensing system. The SNR analysis is helpful for demonstrating the best operation condition for multispectral remote sensing system of this kind, as well as optimizing related optical system parameters for best performance with lowest cost.
付强, 相里斌, 景娟娟. 基于多光谱遥感成像链模型的系统信噪比分析[J]. 光学学报, 2012, 32(2): 0211001. Fu Qiang, Xiangli Bin, Jing Juanjuan. System Signal-to-Noise Ratio Analysis Based on Imaging Chain Model in Multispectral Remote Sensing[J]. Acta Optica Sinica, 2012, 32(2): 0211001.