摘要
由于测量仪器的限制,热辐射方向性测量很难直接获得瞬时方向亮温分布,耗时较长,存在明显的时间效应。目前通常采用线性近似方法纠正,但是无法进行定量误差分析。以冬小麦为例,结合小气候模型CUPID和计算机真实结构模型RGM模拟测量过程中的组分温度和方向亮温变化,对采用线性近似算法进行时间效应纠正的误差进行了评估。结果表明,采用线性近似纠正可以满足测量要求,纠正误差(RMSE)小于0.3K。通过相关性分析得出结论:组分温度时间差异是方向亮温时间差异的主要影响因素。
Limited by the instrument, it is currently difficult to obtain the instantaneous directional brightness temperature （DBT） distribution by measurement. One of the difficulties is the time effect during the measurement process. Usually, linear correction method is used to remove this effect without quantitative error estimation. Taking winter wheat as an example, the time effect on the measurement of thermal emission directionality was analyzed by simulating the variations of component temperature and DBT by coupling a microclimate model CUPID and a three-dimensional DBT model RGM （Radiosity-Graphics Model）. The RMSE of linear correction method was assessed about 0.3K, which was acceptable. From the correlation analysis, it is concluded that the variations of component temperatures are the key factors that affect the accuracy of DBT measurement.
出处
《系统仿真学报》
EI
CAS
CSCD
北大核心
2007年第15期3586-3590,共5页
Journal of System Simulation
基金
国家自然科学基金(40371087)
中国科学院知识创新工程重要方向性项目(KZCX3-SW-338-2)
973项目地球表面时空多变要素的定量遥感理论及应用(G2000077903)
关键词
热辐射方向性
时间效应
方向亮温
组分温度模拟
遥感
thermal emission directionality
time effect
directional brightness temperature
component temperature simulation
remote sensing
