电离层形态对解算GPS系统硬件延迟精度的影响

项目名称： 电离层形态对解算GPS系统硬件延迟精度的影响

项目编号： No.41274156

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 张东和

作者单位： 北京大学

项目金额： 80万元

中文摘要： GPS系统硬件延迟估算是基于GPS数据提取电离层总电子含量过程中的重要步骤，对硬件延迟的估算误差也是基于GPS数据提取电离层总电子含量的主要误差源，对硬件延迟估算结果的分析有助于认识电离层总电子含量的精度和可应用范围。本研究通过分析特殊电离层扰动期间利用GPS数据提取的硬件延迟的变化，明确电离层状态对GPS系统硬件延迟估算的影响；通过对不同空间区域GPS数据提取的硬件延迟的统计分析，定量分析传统硬件延迟估算方法得到的延迟精度；结合电离层随太阳活动周、季节等的变化规律，统计研究电离层长期变化对硬件延迟估算结果的影响规律。通过不同电离层背景和扰动条件下的GPS硬件延迟估算误差，分析基于GPS数据提取电离层总电子含量的精度，分析利用这类数据开展电离层扰动研究的可靠性。考虑电离层对硬件延迟估算结果的影响规律，建立稳定、准确的硬件延迟估算方法，提高基于GPS数据提取电离层总电子含量的精度。

中文关键词： 电离层；全球卫星导航系统；硬件延迟偏差；电离层形态；

英文摘要： The estimation of GPS instrumental bias is one of the most important processes to derive ionospheric total electron content (TEC) from dual-frequency GPS observation. The error of the estimated instrumental bias is also the main error source of the ionospheric TEC derived GPS data. In this project, by the analysis of the variability of instrumental bias derived from GPS data observed during the period of strong ionospheric disturbance, the connection between the variability of instrumental bias and the ionospheric effect will be made. According to the statistical results of GPS instrumental bias derived from GPS data observed at different latitudinal location, the error of bias will be quantitatively studied related to variation of the ionospheric morphology. Considering the features of the ionospheric solar cycle variation, ionospheric seasonal variation, the bias stability and its creditability will be studied. Based on the bias error and bias stability under different ionospheric condition, the analysis of precision of ionospheric TEC derived from GPS data will be done, and the evaluation of results obtained based on this kind of ionospheric TEC will be conducted. Finally, considering the ionospheric effect on the method of bias estimation, a more stable and more accurate estimation method of instrumental bia

英文关键词： ionosphere；GPS；differential code bias；ionospheric morphology；