摘要
信噪比表征光谱成像仪的辐射响应,是与其图像质量密切关联的重要参数。对于机载超光谱成像仪,在保证光谱分辨率的同时,要求其信噪比达到数百量级。有别于单色相机,光谱成像仪的信噪比估算侧重于获得其工作波段内各波长处的信噪比值。仿真实际的拍摄条件,特别引入了入射狭缝对视场限制所引起的信噪比衰减,综合考虑平台高度、太阳高度角、地面反射率等环境因子,利用"中分辨率大气传输模型"建立光信号的大气传输模型。超光谱成像仪的工作波段覆盖可见、近红外范围,同时使用的两个探测器的噪声需分别予以计算。信噪比的估算可作为机载超光谱成像仪总体设计和参数确定的依据。
The signal-to-noise ratio（SNR） of an imaging spectrometer reflects its radiance response and relates closely to its acquired image quality.For an airborne hyperspectral imaging spectrometer,the SNR is required to be in the hundreds while the intentional spectral resolution requirement is met.Varying from panchromatic cameras,for an imaging spectrometer,not a single SNR value but many a value due to different wavelengths has to be worked out.The atmospheric transmission model was built and the shooting circumstance was simulated by use of the MODerate resolution TRANsmission（MODTRAN）.The SNR reduction due to the input throughput cut caused by the entrance slit was taken into account,so are the environmental factors such as flight height,solar altitude angle and surface albedo.Two detectors were adopted for an imaging spectrometer that worked in both visible and near-infrared bands and the noise of each one was calculated individually.The evaluating SNR of the airborne hyperspectral imaging spectrometer can be used as the basis for its overall design and indice determination.
出处
《红外与激光工程》
EI
CSCD
北大核心
2012年第9期2300-2303,共4页
Infrared and Laser Engineering
基金
国家科技部863计划课题(2008AA12120143)
中国地质调查局工作项目(1212011120227)
