摘要
将传感器接收到的信号TOAS(the top of the atmosphere signals)转换成反映地表目标特性的反射信号是遥感信息定量化的关键环节之一。在假定大气干扰已经被排除的条件下,由于像元之间“邻近效应”的存在,被观测目标像元的反射信号(DN值中)包含了背景地物像元散射的贡献。这种贡献的大小与背景像元的反射率值大小成正比,同时与距离目标像元的远近相关。据Carder(1995),Christtopher(1998)等的研究结果,当空间分辨率大于250 m时, “邻近效应”的影响作用超过混合像元影响作用。随着卫星遥感空间分辨率和应用遥感信息定量化程度要求的提高,“邻近效应”及其校正已经开始受到遥感界的重视。近来,我们在国家自然科学基金的支持下,开展这方面的工作。介绍了我们选择北京地区Landsat5 TM数据为例,利用辐射传输模型原理,对影像中存在的“邻近效应”进行了分析和校正,试图理解“邻近效应”的一般影响特征。
The conversion of sensor the top of the atmosphere signals （TOAS）, to reflectivity representing land surface target characters is an important sector in remote sensing information quantification. Assuming atmosphere disturbance being excluded, because of adjacency effect among pixels, the DN value of a target pixel contain the scatter contributions of background pixels. The magnitude of the contribution is directly proportional to the background pixel reflectivity and is correlative with the distance to target pixel. According to the results of carder（1995） and Christopher（1998）, the influence of adjacency effect exceeds that of mixed pixels when the spatial resolution is greater than 250 m. Along with the increase of satellite spatial resolution and remote sensing information quantification degree, adjacency effect and its correction method are paid attention to. Recently, supported by NSFC, we have carried out a research on them. Based on radiation transfer model, the adjacency effect in a scene of Landsat5 TM data of Beijing is analyzed and corrected to comprehend the general characters of adjacency effect.
出处
《量子电子学报》
CAS
CSCD
北大核心
2005年第4期657-662,共6页
Chinese Journal of Quantum Electronics
基金
国家自然科学基金项目(40371086)
