Undifferenced and uncombined PPP-RTK aided by BDS-3 PPP-B2b precise orbits

doi:10.11947/j.AGCS.2023.20220259

Abstract

Abstract: Standard precise point positioning (PPP) service has been provided to users in Asia-Pacific region for free by the BDS-3 through B2b signals of BDS-3's geostationary earth orbit satellites (PPP-B2b), but its long convergence time of approximately 30 minutes and decimeter-level positioning accuracy in real-time processing are not conducive to its subsequent application and promotion. Therefore, this study proposes an enhanced positioning method that integrates precise satellite orbit products of PPP-B2b and observations from the regional sparse reference network, namely the undifferenced and uncombined PPP real-time kinematic (UDUC PPP-RTK) based on the PPP-B2b, and it is further constrained by the between-station single-difference ionospheric delay pseudo-observations to achieve a tight estimation of parameters such as ionospheric delay parameters. Besides, the single-satellite real-time modeling schemes of regional ionospheric slant delays and their accuracy information are emphasis designed in this study, which effectively compresses the amount of broadcast data while improves the application performance of PPP-RTK. Then, some near-real-time experiments have been carried out based on the Beijing-Tianjin sparse reference network to verify above theoretical method. The results show that the correction accuracy of the ionospheric slant delays calculated by the proposed method are 2.2 cm for BDS-3 and 2.4 cm for GPS; the absolute positioning errors of BDS-3+GPS converge to 2 cm (horizontal) and 5 cm (vertical) within 2 s for above 95% of arcs; and the millimeter- (horizontal) and centimeter-level (vertical) positioning accuracy can be achieved after convergence of positioning errors.

Key words: BDS-3, PPP-B2b, undifferenced and uncombined, PPP-RTK, ionospheric slant delay, single-satellite modeling

CLC Number:

P228

ZHA Jiuping, ZHANG Baocheng, LIU Teng, ZHANG Xiao, HOU Pengyu, YUAN Yunbin, LI Zishen. Undifferenced and uncombined PPP-RTK aided by BDS-3 PPP-B2b precise orbits[J]. Acta Geodaetica et Cartographica Sinica, 2023, 52(9): 1449-1459.

References

[1] ZUMBERGE J F, HEFLIN M B, JEFFERSON D C, et al. Precise point positioning for the efficient and robust analysis of GPS data from large networks[J]. Journal of Geophysical Research: Solid Earth, 1997, 102(B3): 5005-5017.
[2] 中国卫星导航系统管理办公室. 北斗卫星导航系统应用服务体系(1.0版)[EB/OL]. [2023-08-11]. http://www.beidou.gov.cn/xt/gfxz/201912/P02019122733281133589 0.pdf. China Satellite Navigation Office. The application service architecture of BeiDou navigation satellite system (version 1.0)[EB/OL]. [2023-08-11]. http://www.beidou.gov.cn/xt/gfxz/201912/P020191227332811335890.pdf.
[3] YANG Yuanxi, LIU Li, LI Jinlong, et al. Featured services and performance of BDS-3[J]. Science Bulletin, 2021, 66(20): 2135-2143.
[4] 中国卫星导航系统管理办公室. 北斗卫星导航系统空间信号接口控制文件精密单点定位服务信号PPP-B2b(1.0 版)[EB/OL]. [2023-08-11]. http://www.beidou.gov.cn/xt/gfxz/202008/P020200803362056878157.pdf. China Satellite Navigation Office. BeiDou navigation satellite system signal in space interface control document open service signal B2b (version 1.0)[EB/OL]. [2023-08-11]. http://www.beidou.gov.cn/xt/gfxz/202008/P020200803362056878157.pdf.
[5] Japan Cabinet Office. Quasi-Zenith satellite system interface specification centimeter level augmentation service (IS-QZSS-L6-003)[EB/OL]. [2023-08-11]. https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-003.pdf.
[6] MONTENBRUCK O, STEIGENBERGER 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.
[7] 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.
[8] LU Xiangchen, CHEN Liang, SHEN Nan, et al. Decoding PPP corrections from BDS B2b signals using a software-defined receiver: an initial performance evaluation[J]. IEEE Sensors Journal, 2020, 21(6): 7871-7883.
[9] TAO Jun, LIU Jingnan, HU Zhigang, et al. Initial assessment of the BDS-3 PPP-B2b RTS compared with the CNES RTS[J]. GPS Solutions, 2021, 25(4): 131.
[10] REN Zhiling, GONG Hang, PENG Jing, et al. Performance assessment of real-time precise point positioning using BDS PPP-B2b service signal[J]. Advances in Space Research, 2021, 68(8): 3242-3254.
[11] YANG Yuanxi, DING Qun, GAO Weiguang, et al. Principle and performance of BDSBAS and PPP-B2b of BDS-3[J]. Satellite Navigation, 2022, 3(1): 5.
[12] ZHANG Weixing, LOU Yidong, SONG Weiwei, et al. Initial assessment of BDS-3 precise point positioning service on GEO B2b signal[J]. Advances in Space Research, 2022, 69(1): 690-700.
[13] YANG Hao, JI Shengyue, WENG Duojie, et al. Assessment of the feasibility of PPP-B2b service for real-time coseismic displacement retrieval[J]. Remote Sensing, 2021, 13(24): 5011.
[14] 易卿武, 蔚保国, 王彬彬, 等. 一种基于北斗三号B2b信号的精密单点授时方法[J]. 电子学报, 2022, 50(4): 832-840. YI Qingwu, YU Baoguo, WANG Binbin,et al. A precise point timing method based on BDS-3 B2b signal[J]. Acta Electronica Sinica, 2022, 50(4): 832-840.
[15] WVBBENA G, SCHMITZ M, BAGGE A. PPP-RTK: precise point positioning using state-space representation in RTK networks[C]// Proceedings of 2005 ION GNSS. Long Beach: ION, 2005: 2584-2594.
[16] GE M, GENDT G, ROTHACHER M, et al. Resolution of GPS carrier-phase ambiguities in precise point positioning (PPP) with daily observations[J]. Journal of Geodesy, 2008, 82(7): 389-399.
[17] LI Xingxing, ZHANG Xiaohong, GE Maorong. Regional reference network augmented precise point positioning for instantaneous ambiguity resolution[J]. Journal of Geodesy, 2011, 85(3): 151-158.
[18] TEUNISSEN P, ODIJK D, ZHANG Baocheng. PPP-RTK: results of CORS network-based PPP with integer ambiguity resolution[J]. Journal of Aeronautics, Astronautics and Aviation(Series A), 2010, 42(4):223-230.
[19] ZHANG Baocheng, TEUNISSEN P J G, ODIJK D. A novel undifferenced PPP-RTK concept[J]. Journal of Navigation, 2011, 64(S1): 180-191.
[20] TEUNISSEN P J G, KHODABANDEH A. Review and principles of PPP-RTK methods[J]. Journal of Geodesy, 2015, 89(3): 217-240.
[21] ZHANG Baocheng, HOU Pengyu, ZHA Jiuping, et al. PPP-RTK functional models formulated with undifferenced and uncombined GNSS observations[J]. Satellite Navigation, 2022, 3(1): 1-15.
[22] ZHANG Baocheng, HOU Pengyu, ZHA Jiuping, et al. Integer-estimable FDMA model as an enabler of GLONASS PPP-RTK[J]. Journal of Geodesy, 2021, 95(8): 1-21.
[23] ODIJK D, ZHANG Baocheng, KHODABANDEH A, et al. On the estimability of parameters in undifferenced, uncombined GNSS network and PPP-RTK user models by means of S-system theory[J]. Journal of Geodesy, 2016, 90(1): 15-44.
[24] PSYCHAS D, VERHAGEN S. Real-time PPP-RTK performance analysis using ionospheric corrections from multi-scale network configurations[J]. Sensors, 2020, 20(11): 3012.
[25] LI Xin, LI Xingxing, HUANG Jiaxin, et al. Improving PPP-RTK in urban environment by tightly coupled integration of GNSS and INS[J]. Journal of Geodesy, 2021, 95(12): 132.
[26] PSYCHAS D. Fast and reliable multi-GNSS precise point positioning with integer ambiguity resolution[D].Delft: Technology University Delft, 2022.
[27] 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.
[28] HE Chengpeng, GU Shengfeng, LIU Cheng, et al. Simulation research on PPP-RTK performance based on BDS GEO satellite[J]. Measurement Science and Technology, 2022, 33(6): 065025.
[29] LI Zhao, CHEN Wu, RUAN Rengui, et al. Evaluation of PPP-RTK based on BDS-3/BDS-2/GPS observations: a case study in Europe[J]. GPS Solutions, 2020, 24(2): 38.
[30] WAN Lihua, WU Xiaomeng, ZHANG Peng, et al. Performance analysis of real-time PPP-RTK with multi-scale enhancement network[C]// Proceedings of 2021 China Satellite Navigation Conference. Singapore: Springer, 2021: 690-704.
[31] ZHA Jiuping, ZHANG Baocheng, LIU Teng, et al. Ionosphere-weighted undifferenced and uncombined PPP-RTK: theoretical models and experimental results[J]. GPS Solutions, 2021, 25(4): 135.
[32] ODIJK D. Fast precise GPS positioning in the presence of ionospheric delays[D]. Delft: Technology University Delft, 2002.
[33] GENG Jianghui, MENG Xiaolin, DODSON A H, et al. Integer ambiguity resolution in precise point positioning: method comparison[J]. Journal of Geodesy, 2010, 84(9): 569-581.
[34] 黄丁发, 周乐韬, 李成钢,等. GPS增强参考站网络理论[M]. 北京: 科学出版社, 2011. HUANG Dingfa, ZHOU Letao, LI Chenggang, et al. Network theory of GPS enhanced reference station[M]. Beijing: Science Press, 2011.
[35] GU Shengfeng, SHI Chuang, LOU Yidong, et al. Ionospheric effects in uncalibrated phase delay estimation and ambiguity-fixed PPP based on raw observable model[J]. Journal of Geodesy, 2015, 89(5): 447-457.