摘要
传感器光谱响应差异是导致不同来源NDVI观测数据之间差异的因素之一,在进行多源遥感数据之间的对比和同化处理时需要对其影响加以分析和校正。基于此,该研究将地物的反射波谱曲线和传感器的光谱响应函数进行卷积,以此来模拟不同传感器在可见光和近红外通道的等效地表反射率并计算相应的NDVI,分别用绝对误差和相对误差两个指标来描述不同传感器观测结果相对于MODIS的差异并建立校正模型。结果表明,光谱响应差异引起的不同传感器观测结果差异可以通过二次多项式模型进行校正,基于相对误差的校正模型比基于绝对误差的校正模型效果更好一些,整体上传感器光谱响应差异对NDVI观测值的影响有限,还需要进一步考虑大气状况及观测几何等其他因素的影响。
Spectral response difference of satellite sensors is one of the factors that is responsible for the difference of measured NDVI from separate sources.There is a strong need for the analysis and calibration of spectral response difference effects when using multi-sensor datasets.Spectral response functions are integrated with a set of reflectance spectra curves to simulate the observations of red and near-infrared bands for different satellite sensors.Absolute difference and relative difference are used to compare the measured data between MODIS and other sensors and establish calibration models.The results show that the difference of observations due to spectral response for separate sensors can be corrected by quadratic polynomial equations.Calibration model based on relative difference performs is better than the absolute difference based model.The overall effects of spectral response difference on measured NDVI are limited and other factors such as atmospheric conditions and observation geometries should be considered further.
出处
《遥感信息》
CSCD
北大核心
2015年第4期91-98,共8页
Remote Sensing Information
基金
国家高技术研究发展计划项目(2012AA12A304)
国家自然科学基金项目(41201184
41271112
41201089)
关键词
光谱响应函数
传感器
反射率
NDVI
校正模型
spectral response function
satellite sensor
reflectance
NDVI
calibration model
