单频GPS实时定位精度分析  

Real-time positioning accuracy analysis of single-frequency GPS based on predicted ionosphere grid products

作　　者：周建[1] 宫萍[1] 吴兴存[1] 虞尚泳 

机构地区：[1]中国卫星海上测控部,江苏江阴214400

出　　处：《测绘科学》2015年第6期151-155,共5页Science of Surveying and Mapping

摘　　要：电离层延迟误差是单频GPS实时/事后定位误差的一个重要来源,目前尚无有效的方法来削弱其影响。针对这一状况,该文首先介绍了单频GPS改正电离层延迟误差的常用方法,通过分析说明了电离层格网数据能够有效改善单频GPS实时/事后定位误差。给出了电离层格网数据的建立、预报方法,并详细介绍了刺入点地心经纬度VTEC值的计算方法、四点格网法内插刺入点天顶方向的总电子含量以及单层模型投影函数。结合算例,分析比较了不同类型电离层改正数据与卫星星历数据对单频GPS实时/事后定位精度的影响。实验结果表明,利用电离层格网预报数据能够显著改善单频GPS的实时/事后导航定位精度,对提高单频GPS定位精度具有一定实用价值。Firstly, this paper introduces the common methods and accounts for the advantage of ionosphere grid products for correcting ionosphere errors with single-frequency GPS, according the analysis that ionosphere grid products can effectively ameliorate errors of single-frequency GPS navigation and positioning. In detail, this article gives the establishment, forecast and operation methods of ionosphere grid products, and introduces the method that calculates the VTEC（Vertical Total Electronic Contents）values of the geocentric latitude of the ionospheric pierce point, the VTEC values of four-point interpolation models and the single-layer mapping function. It also compares different pairs of ionosphere correction data and satellite ephemeris which use to analyze the impact of real-time positioning accuracy of single-frequency GPS The experiments prove that the predicted ionosphere grid products can obviously improve the precision for single-frequency users, and have some practical values for single- frequency positioning and orbit determination.

关 键 词：电离层格网数据 单频GPS 定位精度 卫星星历 

分 类 号：P208[天文地球—地图制图学与地理信息工程]