Sliding window based GNSS dSTEC weighting method for real-time combination of global ionospheric maps

doi:10.11947/j.AGCS.2024.20220351

Abstract

Abstract: Real-time global ionospheric corrections have been provided by several ionospheric analysis centers of the International GNSS Service (IGS) since 2017. Considering the potential unstable ionospheric streams from individual analysis centers in real applications, we propose a sliding window based differential slant total electron content (dSTEC) weighting technique for the combination of real-time global ionospheric maps (RT-GIMs). The combined RT-GIMs are generated using real-time ionospheric streams from the Chinese Academy of Sciences (CAS), Centre National d'Etudes Spatiales (CNES), Polytechnic University of Catalonia (UPC) and Wuhan University (WHU). The performance of combined RT-GIMs is validated during 15 February and 15 March 2022 in both ionospheric correction and positioning domains. The root mean square (RMS) differences between combined RT-GIM and IGS-GIM are 3.30 TECU for our combined one, and 3.20 TECU for UPC combined one. The positioning performance of combined RT-GIMs is also evaluated in ionospheric corrected single-frequency standard point positioning (SF-SPP) and ionospheric constricted single-frequency precise point positioning (SF-PPP), by analyzing the 95% quantile of positioning residuals. Compared to IGS-GIM corrected results, the positioning accuracy of combined RT-GIMs decreases by 7.7% and 4.9% in SF-SPP and SF-PPP analysis, respectively. Compared to BDGIM corrected results, the positioning accuracy of combined RT-GIMs increases by 15.9% in SF-SPP and 9.5% in SF-PPP, respectively. CAS combined RT-GIMs have been routinely provided to the IGS since 2022.

Key words: real-time global ionospheric map, differential slant total electron content, sliding window, real-time combination, real-time service

CLC Number:

P228

WANG Ningbo, LI Zishen, LI Ang, ZHANG Yan, LIU Ang, WANG Liang. Sliding window based GNSS dSTEC weighting method for real-time combination of global ionospheric maps[J]. Acta Geodaetica et Cartographica Sinica, 2024, 53(2): 296-305.

References

[1] 张小红, 李星星, 李盼. GNSS精密单点定位技术及应用进展[J]. 测绘学报, 2017, 46(10):1399-1407.DOI:10.11947/j.AGCS.2017.20170327. ZHANG Xiaohong, LI Xingxing, LI Pan. Review of GNSS PPP and its application[J]. Acta Geodaetica et Cartographica Sinica, 2017, 46(10):1399-1407.DOI:10.11947/j.AGCS.2017.20170327.
[2] 杨宇飞, 杨元喜, 陈金平, 等. 北斗三号星座拟稳钟差测定及其预报[J]. 测绘学报, 2021, 50(12):1728-1737.DOI:10.11947/j.AGCS.2021.20210084. YANG Yufei, YANG Yuanxi, CHEN Jinping, et al. Pseudo-stable constellation bias error of BDS-3 and its high-precision prediction[J]. Acta Geodaetica et Cartographica Sinica, 2021, 50(12):1728-1737.DOI:10.11947/j.AGCS.2021.20210084.
[3] MONTENBRUCK O, STEIGENBEBERGER P, PRANGE L, et al. The multi-GNSS experiment (MGEX) of the International GNSS Service (IGS)-achievements, prospects and challenges[J]. Advances In Space Research, 2017, 59(7):1671-1697.
[4] YANG Yuanxi, MAO Yue, SUN Bijiao. Basic performance and future developments of BeiDou global navigation satellite system[J]. Satellite Navigation, 2020, 1(1):1-8.
[5] 蔡洪亮, 孟轶男, 耿长江, 等. 北斗三号全球导航卫星系统服务性能评估:定位导航授时、星基增强、精密单点定位、短报文通信与国际搜救[J]. 测绘学报, 2021, 50(4):427-435.DOI:10.11947/j.AGCS.2021.20200549. CAI Hongliang, MENG Yinan, GENG Changjiang, et al. BDS-3 performance assessment:PNT, SBAS,PPP, SMC and SAR[J]. Acta Geodaetica et Cartographica Sinica, 2021, 50(4):427-435.DOI:10.11947/j.AGCS.2021.20200549.
[6] LIU Cheng, GAO Weiguang,LIU Tianxiong, et al. Design and implementation of a BDS precise point positioning service[J]. Navigation, 2020, 67(4):875-891.
[7] 袁运斌, 霍星亮, 张宝成. 近年来我国GNSS电离层延迟精确建模及修正研究进展[J]. 测绘学报, 2017, 46(10):1364-1378.DOI:10.11947/j.AGCS.2017.20170349. YUAN Yunbin, HUO Xingliang, ZHANG Baocheng. Research progress of precise models and correction for GNSS ionospheric delay in China over recent years[J]. Acta Geodaetica et Cartographica Sinica, 2017, 46(10):1364-1378.DOI:10.11947/j.AGCS.2017.20170349.
[8] 张小红, 胡家欢, 任晓东. PPP/PPP-RTK新进展与北斗/GNSS PPP定位性能比较[J]. 测绘学报, 2020, 49(9):1084-1100.DOI:10.11947/j.AGCS.2020.20200328. ZHANG Xiaohong, HU Jiahuan, REN Xiaodong. New progress of PPP/PPP-RTK and positioning performance comparison of BDS/GNSS PPP[J]. Acta Geodaetica et Cartographica Sinica, 2020, 49(9):1084-1100.DOI:10.11947/j.AGCS.2020.20200328.
[9] 李子申, 王宁波, 李亮, 等. 北斗高精度高可信PPP-RTK服务基本框架[J]. 导航定位与授时, 2023,10(2):7-15. LI Zishen, WANG Ningbo, LI Liang, et al. Basic framework of BDS-based high-precision and high-credibility PPP-RTK service[J]. Navigation Positioning and Timing, 2023, 10(2):7-15.
[10] LI Zishen, WANG Ningbo, HERNANDEZ-PAJARES M, et al. IGS real-time service for global ionospheric total electron content mo-deling[J]. Journal of Geodesy, 2020, 94(3):1-16.
[11] LI Zishen, WANG Ningbo, LIU Ang, et al. Status of CAS global ionospheric maps after the maximum of solar cycle 24[J]. Satellite Navigation, 2021, 2(1):1-15.
[12] YANG H, MONTE-MORENO E, HERNANDEZ-PAJARES M, et al. Real-time interpolation of global ionospheric maps by means of sparse representation[J]. Journal of Geodesy, 2021, 95(6):115-128.
[13] LIU Ang, LI Zishen, WANG Ningbo, et al. SHAKING:adjusted spherical harmonics adding Kriging method for near real-time ionospheric modeling with multi-GNSS observations. [J]. Chinese Journal of Geophysics, 2023,71(1):67-79.
[14] 李子申, 王宁波, 李敏, 等. 国际GNSS服务组织全球电离层TEC格网精度评估与分析[J]. 地球物理学报, 2017, 60(10):3718-3729. LI Zishen, WANG Ningbo, LI Min, et al. Evaluation and analysis of the global ionospheric TEC map in the frame of international GNSS services[J]. Chinese Journal of Geophysics, 2017, 60(10):3718-3729.
[15] NIE Zhixi, YANG Hongzhou, ZHOU Peiyuan, et al. Quality assessment of CNES real-time ionospheric products[J]. GPS Solutions, 2019, 23(1):1-15.
[16] REN Xiaodong, CHEN Jun, LI Xingxing, et al. Performance evaluation of real-time global ionospheric maps provided by different IGS analysis centers[J]. GPS Solutions, 2019, 23(4):1-17.
[17] ERDOGAN E, SCHMIDT M, GOSS A, et al. Real-time monitoring of ionosphere VTEC using multi-GNSS carrier-phase observations and B-splines [J].Space Weather, 2021, 19(10):1-17.
[18] HERNANDEZ-PAJARES M, ROMA-DOLLASE D, KRANKOWSKI A, et al. Methodology and consistency of slant and vertical assessments for ionospheric electron content models[J]. Journal of Geodesy, 2017, 91(12):1405-1414.
[19] LIU Qi, HERNANDEZ-PAJARES M, YANG Heng, et al. The cooperative IGS RT-GIMs:a reliable estimation of the global ionospheric electron content distribution in real time[J]. Earth System Science Data, 2021, 13(9):4567-4582.
[20] LIU Ang, WANG Ningbo, DETTMERING D, et al. Using DORIS data for validating real-time GNSS ionosphere maps[J]. Advances in Space Research, 2023, 72(1):115-128.
[21] 舒宝, 王利, 张勤, 等. SSR延迟下的轨道钟差外推误差及其对多GNSS实时精密单点定位的影响评估[J]. 测绘学报, 2021, 50(12):1738-1750. DOI:10.11947/j.AGCS.2021.20200580. SHU Bao, WANG Li, ZHANG Qin, et al. Evaluation of multi-GNSS orbit and clock extrapolating error and their influence on real-time PPP during outages of SSR correction[J]. Acta Geodaetica et Cartographica Sinica, 2021, 50(12):1738-1750. DOI:10.11947/j.AGCS.2021.20200580.
[22] 袁运斌, 李敏, 霍星亮, 等. 北斗三号全球导航卫星系统全球广播电离层延迟修正模型(BDGIM)应用性能评估[J]. 测绘学报, 2021, 50(4):436-447. DOI:10.11947/j.AGCS.2021.20200421. YUAN Yunbin, LI Min, HUO Xingliang, et al. Research on performance of BeiDou global broadcast ionospheric delay correction model (BDGIM) of BDS-3[J]. Acta Geodaetica et Cartographica Sinica, 2021, 50(4):436-447. DOI:10.11947/j.AGCS.2021.20200421.
[23] YUAN Yunbin, WANG Ningbo, LI Zishen, et al. The BeiDou global broadcast ionospheric delay correction model (BDGIM) and its preliminary performance evaluation results[J]. Navigation, 2019, 66(1):55-69.
[24] WANG Ningbo, LI Zishen, YUAN Yunbin, et al. BeiDou global ionospheric delay correction model (BDGIM):performance analysis during different levels of solar conditions[J]. GPS Solutions, 2021, 25(3):97.
[25] ZHAO Jiaojiao, HERNANDEZ-PAJARES M, LI Zishen, et al. Integrity investigation of global ionospheric TEC maps for high-precision positioning [J]. Journal of Geodesy, 2021, 95(3):1-15.