在大气折射延迟模型中避免采用大气分布模型的论证  

The argumentation on avoiding adopted atmospheric distributing model in refraction delay model

作　　者：张捍卫[1] 冒蔚[1] 李彬华[2] 杨磊[1] 铁琼仙[1] 

机构地区：[1]中国科学院国家天文台云南天文台 [2]昆明理工大学信息工程与自动化学院,昆明650051

出　　处：《测绘科学》2007年第1期14-17,共4页Science of Surveying and Mapping

基　　金：江苏省高校自然科学基金项目(06KJB420111)资助

摘　　要：天文大气折射是经典天体测量学和大地测量的一项误差源,大气折射延迟是空间大地测量技术中的一项重要误差源,它们的改正模型都直接与大气折射率和大气分布模型有关。文章简述了大气的垂直分布状况,以及大气折射率(或折射率差)因地和因方位而异的情况,分析了目前只能采用球对称大气分布模型的原因。论证了随测站和随方位而异的天文大气折射和电磁波大气折射延迟实测模型建立的必要性和可能性。实测模型已经包含了测站上空大气实际分布及其非球对称的特性,不必再去寻找或建立随地势而异和随季节而变的大气分布模型,避免了大气分布模型选择不当的影响,从而排除了空间大地测量技术中的一项主要误差源。The astronomical atmospheric refraction is an error source in classical astrometry and geodesy.The refraction delay is a very important error source in techniques of space geodesy.Their correction models are directly related to the atmospheric refractive index and the atmosphere distribution model.This paper simply reviews the circs of atmosphere upright distributing,as well as the status of atmospheric index or refractivity that be different with the station and azimuth,and analyzes the reason why can we adopt spherical symmetry atmosphere model at present.At the same time,it demonstrates the feasibility and necessity to construct the surveying model according to different station and azimuth,which can survey astronomical atmosphere refraction and refraction delay of electromagnetic wave.Because the surveying model has considered the actual distribution of atmosphere above station and the characteristic of non-sphere symmetry of atmosphere,it isn't necessary to searching or constituting the atmosphere distribution model according to topography and season.The surveying model has avoided the effect of unsuitable atmosphere model.Consequently,it excluded an important error source in space geodesy.

关 键 词：大气分布模型 非球对称 大气折射 折射延迟 

分 类 号：P22[天文地球—大地测量学与测量工程]