组分权重方法对城市目标方向亮温模拟的影响  

Impacts of Different Components' Proportion Determination Methods on Directional Brightness Temperature Simulation for Urban Targets

作　　者：占文凤[1,2] 陈云浩[1,2] 马伟[1,2] 周纪[1,2] 

机构地区：[1]北京师范大学地表过程与资源生态国家重点实验室 [2]北京师范大学资源学院

出　　处：《武汉大学学报（信息科学版）》2010年第4期436-440,共5页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金资助项目(4077113640701114);北京市优秀人才培养计划资助项目(20081D0503100254)

摘　　要：借鉴了现阶段二维垄行作物的组分权重确定方法并将其推广到三维城市地表,加上已有的针对城市地表的方法,得到了辐射度方法、水平面投影法、球面投影法和中心投影实验法4种方法。结果表明,当天顶角较小时,辐射度方法、球面投影法、中心投影实验法(通过数码像片勾绘统计计算得到组分权重)和水平面投影法都能较为精确地模拟方向亮温的空间分布。Directional brightness temperature （DBT） plays an important role in surface energy balance and urban climate. Determination of components＇ proportion is one of the key factors to accurate simulation of DBT. An overview of the main components＇ proportion determination methods used currently on urban surfaces was unfolded and some techniques utilized in row crops were expanded to adapt three dimensional urban targets, achieving radiosity method, horizontal projection method, oblique projection method and center projection method. Comparison between those above mentioned four components＇ proportion determination methods demonstrate that they simulate the spatial distribution of DBT perfectly when the zenith angle is small. The result also shows that it is feasible to compute the components＇ proportion through sketching and calculating on the photograph filmed by a digital camera located near the thermal infrared sensor （center projection method）. However, the horizontal projection method is an exception, which has a low precision corresponding to DBT when the zenith angle increased or differences between components＇ temperature extended to a higher level. Finally, a comparative study was conducted on simulation accuracies and complexities of different methods and some specific recommendations were given for diverse needs.

关 键 词：热红外遥感 组分权重 方向亮温 城市地表 辐射度 

分 类 号：P237.3[天文地球—摄影测量与遥感]