一种基于GNSS全系统全频点观测的多路径修正及定位模型

A GNSS System-Wide and Frequency-Wide Integrated Multipath Mitigation and Positioning Model

  • 摘要: 多频多模全球导航卫星系统(global navigation satellite system, GNSS)技术为高性能位置服务提供重要支撑,然而当前定位模型处理中并未有效顾及GNSS全星座全频点观测信息。针对传统GNSS参数估计模型中采用固定组合而忽略了多频观测信息的问题,提出了一种基于GNSS全系统全频点观测的多路径误差修正及定位模型。首先,在观测数据预处理中提取伪距多路径误差多频组合量,克服观测噪声与电离层误差影响并实现伪距多路径误差快速消除;其次,以GNSS全系统全频点观测数据为基础,建立各系统内多频无电离层组合观测方程,实现用户端多频观测信息的充分建模处理;最后,基于GNSS多系统观测数据,构建全系统全频点组合定位数学模型。GNSS静态与动态观测数据实验结果表明:GNSS多频观测信息可实现伪距多路径误差的快速处理,尤其是在动态条件下,基于GNSS全系统全频点观测的伪距多路径误差消除策略具有显著优势;在GNSS多频联合定位模型中,多频最优组合策略的动态定位精度较传统北斗三号卫星导航系统双频东、北、天方向分别提升了81.3%、16.7%与79.0%,且收敛时间显著缩短。

     

    Abstract:
    Objectives It is suggested that the multi-frequency global navigation satellite system (GNSS) technology powerfully accelerate the development of high-performance location services. However, the information of multi-frequency and all-system GNSS observations is not fully used in the processing of positioning parameters. Due to that the fixed combination model used in the traditional GNSS precise point positioning (PPP) solution, the multi-frequency observations are ignored in the parameters estimation. A GNSS system-wide and frequency-wide integrated multipath error mitigation and positioning model is used to improve the PPP performances.
    Methods First, a code multipath error estimation model is designed by the combination of the multi-frequency observations in the stage of observations preprocessing, where the impacts of observation noise and ionospheric error are eliminated. Second, the multi-frequency ionosphere-free combination is constructed in each system based on the GNSS observations of whole systems and all frequencies to fully model the multi-frequency observations of the users received. Third, integrated GNSS multi-system observations, the mathematical model of the whole systems and frequencies combined positioning solution is constructed.
    Results According to the experiments of GNSS static and kinematics observations, it is indicated that GNSS multi-frequency observations can quickly mitigate the code multipath error, especially in the kinematics conditions, where the advantages of multi-frequency observations are significantly presented. In the kinematics positioning solutions, compared with traditional BeiDou-3 navigation satellite system dual-frequency kinematics PPP, the east, north and up directions can be improved with 81.3%, 16.7% and 79.0%, respectively, by the GNSS multi-frequency combined strategy. Moreover, the convergence time is significantly shortened.
    Conclusions Therefore, it is meaningful to use the proposed multi-GNSS and multi-frequency PPP solution, which can promote the improvement of GNSS location services.

     

/

返回文章
返回