摘要
为了适应风云气象卫星遥感数据高精度地理定位要求,在研究和比较分析现有环境气象卫星遥感数据地理定位方法,尤其对其中关键的轨道计算模型进行对比研究之后,我们使用变阶变步长多步卫星轨道数值计算模型(DE/DEABM)进行气象卫星轨道计算,研制开发了新一代卫星轨道计算及遥感数据地理定位软件系统。该软件系统中卫星轨道数值积分计算模型包含了多项摄动因素计算,特别是对低轨卫星影响较大的因素,其中地球的球形引力项使用了高精度高阶EGM-96地球引力场模型,提高了非球形引力摄动计算精度,另外还考虑了太阳、月亮引力项,辐射光压摄动和大气摄动因素,使得轨道计算精度大大提高。在遥感数据定位算法开发工作中,以中国2002年5月发射的风云1号D星10通道扫描辐射计和计划2008年上半年发射的风云3号A卫星中分辨率光谱成像仪等遥感仪器为对象,比较详细地分析和研究了探测器、焦平面、主光学系统和扫描镜等遥感仪器几大关键部件的光学几何关系,提高了坐标转换系统计算精度。经过对风云1号D星多天逐日的轨道计算和定位计算试验,结果表明该软件系统24h风云1号D星轨道计算卫星矢径精度可达到几十厘米至几十米,较原来平根数分析解方法1000m左右精度有显著量级的提高。同时,风云1号D星遥感数据地理定位精度达到星下点1个像元。
In the program of geolocation with environmental meteorological satellite,the earth location software makes use of earth ellipsoid and terrain surface data in conjunction with satellite orbit parameter and geometry attitude,and information of the sensor and satellite geometry to compute data including geodetic longitude and latitude coordinates,height,ground to satellite direction vector and range,and solar vector.The satellite orbit propagation model and the mathematical procedure which intersects the sensor's line of sight with the terrain surface of the Earth are most important in the program.In order to meet the requirement of high precision geolocation for environmental satellite remote sensing data,we have developed a new generation orbital motion forecast and remote sensing geolocation software system.This system is based on the variable order,and stepsize orbital motion numerical integration model(DE/DEABM),and is different from conventional Brouwer perturbation analytical model.During the research of this system,we have studied variety of perturbations that affect orbital motion.These perturbations are pronounced for satellite at low altitudes.We use high order precise EGM-96(Earth gravity model) data to improve computing precision of perturbation for asphericity of the Earth.What we put into consideration also includes the perturbation that arises from the gravitational attraction of the Sun and the Moon,solar radiation pressure and atmospheric drag in our works.As case studies,we develop Earth location algorithms and software for two sensors,one is FY-1D VIRR launched on May 2002,and the other is FY-3A MERSI which will be launched in early 2008.In the progress,we analyse details of the optics geometry coordinates relationship of detector,focal plane,main optics system and scan mirror,which are key parts of sensors.As a result,the precision of coordinates transformation model have been developed in this software.After several days of data computing of orbital motion and Earth location test for FY-1D VIR
出处
《遥感学报》
EI
CSCD
北大核心
2008年第2期312-321,共10页
NATIONAL REMOTE SENSING BULLETIN
基金
国家高技术研究发展计划(863计划)支持课题(编号:2001AA135060,2003AA133050)
关键词
风云卫星
轨道数值积分模型
卫星遥感数据定位
FY-1D satellite
orbit numerical integration model
satellite remote sensing data geolocation
