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Real-Time Precise Point Positioning (RTPPP) with raw observations and its application in real-time regional ionospheric VTEC modeling

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Abstract

Precise Point Positioning (PPP) is an absolute positioning technology mainly used in post data processing. With the continuously increasing demand for real-time high-precision applications in positioning, timing, retrieval of atmospheric parameters, etc., Real-Time PPP (RTPPP) and its applications have drawn more and more research attention in recent years. This study focuses on the models, algorithms and ionospheric applications of RTPPP on the basis of raw observations, in which high-precision slant ionospheric delays are estimated among others in real time. For this purpose, a robust processing strategy for multi-station RTPPP with raw observations has been proposed and realized, in which real-time data streams and State-Space-Representative (SSR) satellite orbit and clock corrections are used. With the RTPPP-derived slant ionospheric delays from a regional network, a real-time regional ionospheric Vertical Total Electron Content (VTEC) modeling method is proposed based on Adjusted Spherical Harmonic Functions and a Moving-Window Filter. SSR satellite orbit and clock corrections from different IGS analysis centers are evaluated. Ten globally distributed real-time stations are used to evaluate the positioning performances of the proposed RTPPP algorithms in both static and kinematic modes. RMS values of positioning errors in static/kinematic mode are 5.2/15.5, 4.7/17.4 and 12.8/46.6 mm, for north, east and up components, respectively. Real-time slant ionospheric delays from RTPPP are compared with those from the traditional Carrier-to-Code Leveling (CCL) method, in terms of function model, formal precision and between-receiver differences of short baseline. Results show that slant ionospheric delays from RTPPP are more precise and have a much better convergence performance than those from the CCL method in real-time processing. 30 real-time stations from the Asia-Pacific Reference Frame network are used to model the ionospheric VTECs over Australia in real time, with slant ionospheric delays from both RTPPP and CCL methods for comparison. RMS of the VTEC differences between RTPPP/CCL method and CODE final products is 0.91/1.09 TECU, and RMS of the VTEC differences between RTPPP and CCL methods is 0.67 TECU. Slant Total Electron Contents retrieved from different VTEC models are also validated with epoch-differenced Geometry-Free combinations of dual-frequency phase observations, and mean RMS values are 2.14, 2.33 and 2.07 TECU for RTPPP method, CCL method and CODE final products, respectively. This shows the superiority of RTPPP-derived slant ionospheric delays in real-time ionospheric VTEC modeling.

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References

  • Bisnath S, Gao Y (2007) Current state of precise point positioning and future prospects and limitations. Observing our changing planet. IAG Symp 133:615–624

    Google Scholar 

  • Choy S, Bisnath S, Rizos C (2017) Uncovering common misconceptions in GNSS Precise Point Positioning and its future prospect. GPS Solut 21(1):13–22

    Article  Google Scholar 

  • Colombo OL (2008) Real-time, wide-area, precise kinematic positioning using data from internet NTRIP streams. In: Proceedings of ION-GNSS-2008, Institute of Navigation, Savannah, Georgia, pp 327–337

  • Ciraolo L, Azpilicueta F, Brunini C et al (2007) Calibration errors on experimental slant total electron content (TEC) determined with GPS. J Geod 81(2):111–120

    Article  Google Scholar 

  • Defraigne P, Baire Q, Guyennon N (2007) GLONASS and GPS PPP for time and frequency transfer. In: Frequency control symposium, 2007 joint with the 21st European frequency and time forum. IEEE international, pp 909–913

  • Elsobeiey M, Al-Harbi S (2016) Performance of real-time Precise Point Positioning using IGS real-time service. GPS Solut 20(3):565–571

    Article  Google Scholar 

  • Feltens J (2003) The activities of the ionosphere working group of the International GPS Service (IGS). GPS Solut 7(1):41–46

    Article  Google Scholar 

  • Feltens J, Angling M, Jackson-Booth N et al (2011) Comparative testing of four ionospheric models driven with GPS measurements. Radio Sci 46(6):1–11

    Article  Google Scholar 

  • Ge M, Chen J, Douša J et al (2012) A computationally efficient approach for estimating high-rate satellite clock corrections in realtime. GPS Solut 16(1):9–17

    Article  Google Scholar 

  • Gu S, Lou Y, Shi C et al (2015) BeiDou phase bias estimation and its application in precise point positioning with triple-frequency observable. J Geod 89(10):979–992

    Article  Google Scholar 

  • Guo F, Zhang X, Wang J et al (2016) Modeling and assessment of triple-frequency BDS precise point positioning. J Geod 90(11):1223–1235

    Article  Google Scholar 

  • Hadas T, Bosy J (2015) IGS RTS precise orbits and clocks verification and quality degradation over time. GPS Solut 19(1):93–105

    Article  Google Scholar 

  • Haines G (1988) Computer programs for spherical cap harmonic analysis of potential and general fields. Comput Geosci 14(4):413–447

    Article  Google Scholar 

  • Hernández-Pajares M, Juan JM, Sanz J et al (2009) The IGS VTEC maps: a reliable source of ionospheric information since 1998. J Geod 83(3–4):263–275

    Article  Google Scholar 

  • Hernández-Pajares M, Juan JM, Sanz J et al (2011) The ionosphere: effects, GPS modeling and the benefits for space geodetic techniques. J Geod 85(12):887–907

    Article  Google Scholar 

  • Kouba J, Héroux P (2001) Precise point positioning using IGS orbit and clock products. GPS Solut 5(2):12–28

    Article  Google Scholar 

  • Kuo C, Chiu K, Chiang K et al (2012) High-frequency sea level variations observed by GPS buoys using precise point positioning technique. Terr Atmos Ocean Sci 23(2):209–218

    Article  Google Scholar 

  • Lou Y, Zheng F, Gu S, Wang C, Guo H, Feng Y (2016) Multi-GNSS precise point positioning with raw single-frequency and dual-frequency measurement models. GPS Solut 20(4):849–86

    Article  Google Scholar 

  • Li X, Ge M, Zhang X, Zhang Y, Guo B, Wang R, Klotz J, Wickert J (2013) Real-time high-rate co-seismic displacement from ambiguity-fixed precise point positioning: application to earthquake early warning. Geophys Res Lett 40(2):295–300

    Article  Google Scholar 

  • Li X, Ge M, Dai X, Ren X, Fritsche M, Wickert J, Schuh H (2015a) Accuracy and reliability of multi-GNSS real-time precise positioning: GPS, GLONASS, BeiDou, and Galileo. J Geod 89(6):607–635

    Article  Google Scholar 

  • Li X, Dick G, Lu C et al (2015b) Multi-GNSS meteorology: real-time retrieving of atmospheric water vapor from BeiDou, Galileo, GLONASS, and GPS observations. IEEE Trans Geosci Remote Sens 53(12):6385–6393

    Article  Google Scholar 

  • Li Z (2012) Study on the mitigation of ionospheric delay and the monitoring of global ionospheric TEC based on GNSS/compass. Ph. D. thesis, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan, China (in Chinese)

  • Li Z, Yuan Y, Wang N et al (2015c) SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions. J Geod 89(4):331–345

    Article  Google Scholar 

  • Liu T, Yuan Y, Zhang B et al (2017) Multi-GNSS Precise Point Positioning (MGPPP) using raw observations. J Geod 91(3):253–268

    Article  Google Scholar 

  • Mannucci A, Wilson B, Yuan D, Ho C, Lindqwister U, Runge T (1998) A global mapping technique for GPS-derived ionospheric total electron content measurements. Radio Sci 33(3):565–582

    Article  Google Scholar 

  • Marques HA, Monico JFG, Aquino M (2011) RINEX_HO: second-and third-order ionospheric corrections for RINEX observation files. GPS Solut 15(3):305–31

    Article  Google Scholar 

  • Montenbruck O, Hauschild A, Steigenberger P (2014) Differential code bias estimation using multi-GNSS observations and global ionosphere maps. Navigation 61(3):191–201

    Article  Google Scholar 

  • Rovira-Garcia A, Juan J, Sanz J et al (2016) Accuracy of ionospheric models used in GNSS and SBAS: methodology and analysis. J Geod 90(3):229–240

    Article  Google Scholar 

  • Schaer S (1999) Mapping and predicting the earth’s ionosphere using the global positioning system. Ph.D Dissertation, University of Berne, Switzerland

  • Shi C, Fan L, Li M et al (2016) An enhanced algorithm to estimate BDS satellite’s differential code biases. J Geod 90(2):161–177

    Article  Google Scholar 

  • Tegedor J, Øvstedal O (2014) Triple carrier precise point positioning (PPP) using GPS L5. Surv Rev 46(337):288–297

    Article  Google Scholar 

  • Teunissen P (1985) Generalized inverses, adjustment, the datum problem and S-transformations. In: Sanso F, Grafarend EW (eds) Optimization of geodetic networks. Springer, Berlin, pp 11–55

    Chapter  Google Scholar 

  • Teunissen P, Khodabandeh A (2015) Review and principles of PPP-RTK methods. J Geod 89(3):217–240

    Article  Google Scholar 

  • Weber G, Mervart L, Lukes Z, Rocken C, Dousa J (2007) Real-time clock and orbit corrections for improved point positioning via NTRIP. In: Proceedings of ION-GNSS-2007, Institute of Navigation, 25–28 Sept, Fort Worth, TX, USA, pp 1992–1998

  • Zhang B, Ou J, Yuan Y, Li Z (2012) Extraction of line-of-sight ionospheric observables from GPS data using precise point positioning. Sci China Earth Sci 55(11):1919–1928

    Article  Google Scholar 

  • Zhang B (2016) Three methods to retrieve slant total electron content measurements from ground-based GPS receivers and performance assessment. Radio Sci 51(7):972–988

    Article  Google Scholar 

  • Zhang X, Andersen O (2006) Surface Ice flow velocity and tide retrieval of the Amery ice shelf using precise point positioning. J Geod 80(4):171–176

    Article  Google Scholar 

  • Zumberge J, Heflin M, Jefferson D, Watkins M, Webb F (1997) Precise point positioning for the efficient and robust analysis of GPS data from large networks. J Geophys Res 102(B3):5005–5017

    Article  Google Scholar 

Download references

Acknowledgements

The authors would like to acknowledge the IGS, GA (Geoscience Australia), CNES and CODE for providing access to the real-time data streams, SSR satellite orbit and clock corrections, post-processed DCB and GIM products. We would like to express our great appreciation to Weixin He for kindly providing the IGG NTRIP software and related technical supports. Funding supports from Collaborative Precision Positioning Project funded by Ministry of Science and Technology of China (No. 2016YFB0501900) and China Natural Science Funds (Nos. 41231064, 41674022, 41621091) are also gratefully acknowledged. The second author is supported by the CAS Pioneer Hundred Talents Program.

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  1. State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, 340 Xudong Rd., Wuhan, 430077, People’s Republic of China

    Teng Liu, Baocheng Zhang, Yunbin Yuan & Min Li

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  1. Teng Liu
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  2. Baocheng Zhang
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  3. Yunbin Yuan
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  4. Min Li
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Correspondence to Baocheng Zhang.

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Liu, T., Zhang, B., Yuan, Y. et al. Real-Time Precise Point Positioning (RTPPP) with raw observations and its application in real-time regional ionospheric VTEC modeling. J Geod 92, 1267–1283 (2018). https://doi.org/10.1007/s00190-018-1118-2

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  • DOI: https://doi.org/10.1007/s00190-018-1118-2

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