Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-25T05:50:15.740Z Has data issue: false hasContentIssue false
  • English
  • Français

Real-Time Precise Point Positioning Using Orbit and Clock Corrections as Quasi-Observations for Improved Detection of Faults

Published online by Cambridge University Press:  05 February 2018

Ahmed El-Mowafy
Ahmed El-Mowafy*
Affiliation:
(Department of Spatial Sciences, Curtin University, Australia)
*
(E-mail: [email protected])
Get access Rights & Permissions [Opens in a new window]

Abstract

Real-time Precise Point Positioning (PPP) relies on the use of accurate satellite orbit and clock corrections. If these corrections contain large errors or faults, either from the system or by meaconing, they will adversely affect positioning. Therefore, such faults have to be detected and excluded. In traditional PPP, measurements that have faulty corrections are typically excluded as they are merged together. In this contribution, a new PPP model that encompasses the orbit and clock corrections as quasi-observations is presented such that they undergo the fault detection and exclusion process separate from the observations. This enables the use of measurements that have faulty corrections along with predicted values of these corrections in place of the excluded ones. Moreover, the proposed approach allows for inclusion of the complete stochastic information of the corrections. To facilitate modelling of the orbit and clock corrections as quasi-observations, International Global Navigation Satellite System Service (IGS) real-time corrections were characterised over a six-month period. The proposed method is validated and its benefits are demonstrated at two sites using three days of data.

Keywords

PPPGNSSReal-timeFault Detection and Exclusion (FDE)
Type
Research Article
Information
The Journal of Navigation , Volume 71 , Issue 4 , July 2018 , pp. 769 - 787
Copyright
Copyright © The Royal Institute of Navigation 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Aydin, C. and Demirel, H. (2005). Computation of Baarda's lower bound of the non-centrality parameter. Journal of Geodesy, 78 (7-8), 437–441.Google Scholar
Baarda, W.A. (1968). A testing procedure for use in geodetic networks, Netherlands Geodetic Commission, Publications on Geodesy, New Series, 2(5).Google Scholar
Blanch, J., Walter, T., Enge, P., Wallner, S., Fernandez, F.A., Dellago, R., Ioannides, R., Hernandez, I.F., Belabbas, B., Spletter, A. and Rippl, M. (2013). Critical Elements for a Multi-Constellation Advanced RAIM. Navigation, 60(1), 53–69.Google Scholar
Caissy, M, Agrotis, L, Weber, G, Hernandez-Pajares, M. and Hugentobler, U. (2012). Innovation: The International GNSS Real-Time Service. GPS World, 23(6): 52–58.Google Scholar
De Bakker, P.F., Van der Marel, H and Teunissen, P.J.G. (2009). The Minimal Detectable Bias for GNSS Observations with a Single Receiver Setup and a Geometry-Free Mode. Proceedings of ENC-GNSS 2009, Naples, Italy, 3–6 May 2009.Google Scholar
Deo, M. and El-Mowafy, A. (2017). Triple-frequency GNSS models for PPP with float ambiguity estimation: performance comparison using GPS. Survey Review. Available online, doi.org/10.1080/00396265.2016.1263179.Google Scholar
Dow, J.M., Neilan, R.E. and Rizos, C. (2009). The International GNSS Service in a changing landscape of Global Navigation Satellite Systems. Journal of Geodesy, 83, 191–198.Google Scholar
El-Mowafy, A. (2014). GNSS Multi-frequency Receiver Single-Satellite Measurement Validation Method. GPS Solutions, 18, 553–561.Google Scholar
El-Mowafy, A. (2015a). Diagnostic Tools Using a Multi-Constellation Single-Receiver Single-Satellite Data Validation Method. Journal of Navigation, 68(1), 196–214.Google Scholar
El-Mowafy, A. (2015b). Estimation of Multi-Constellation GNSS Observation Stochastic Properties Using a Single-Receiver Single-Satellite Data Validation Method. Survey Review, 47(341), 99–108.Google Scholar
El-Mowafy, A., Deo, M. and Rizos, C. (2016). On Biases in Precise Point Positioning with Multi-Constellation and Multi-Frequency GNSS Data. Measurement Science and Technology, 27(3), 035102.Google Scholar
El-Mowafy, A., Deo, M. and Kubo, N. (2017). Maintaining real-time precise point positioning during outages of orbit and clock corrections. GPS Solutions, 21(3), 937–947.Google Scholar
El-Mowafy, A. (2017). Advanced Receiver Autonomous Integrity Monitoring Using Triple Frequency Data with a Focus on Treatment of Biases. Advances in Space Research, 59(8), 2148–2157.Google Scholar
Hadas, T. and Bosy, J. (2015). IGS RTS precise orbits and clocks verification and quality degradation over time. GPS Solutions, 19(1), 93–105.Google Scholar
Joerger, M., Chan, F. and Pervan, P. (2014). Solution Separation Versus Residual-Based RAIM. Navigation, 61(4), 273–291.CrossRefGoogle Scholar
Kouba, J. and Héroux, P. (2001). Precise point positioning using IGS orbit and clock products. GPS Solutions, 5, 12–28.Google Scholar
Leandro, R., Landau, H., Nitschke, M., Glocker, M., Seeger, S., Chen, X., Deking, A., BenTahar, M., Zhang, F., Ferguson, K., Stolz, R., Talbot, N., Lu, G., Allison, T., Brandl, M., Gomez, V., Cao, W. and Kipka, A. (2011) RTX Positioning: The Next Generation of cm-accurate Real-Time GNSS Positioning. Proc. ION GNSS+ 2011, Institute of Navigation, Portland, 20 – 23 September: 1460 – 1475.Google Scholar
Li, T., Wang, J. and Laurichesse, D. (2014). Modelling and quality control for reliable precise point positioning integer ambiguity resolution with GNSS modernization, GPS Solutions, 18(3), 429–442.Google Scholar
Misra, P. and Enge, P. (2006). Global Position System: Signals, Measurements, and Performance. Revised 2nd edition, Ganga-Jamuna Press, Lincoln, Massachusetts.Google Scholar
Mozo, Álvaro, Calle, J.D., Navarro, P., Piriz, R., Rodriguez, D. and Tobias, G. (2012). Demonstrating in-the-field real-time precise positioning, Proc ION GNSS+ 2012, Institute of Navigation, Nashville, 17 – 21 September: 3066–3076.Google Scholar
Montenbruck, O. and Hauschild, A. (2013). Code biases in multi-GNSS point positioning, Proceedings of ION-ITM 2013, San Diego, 28–30 January 2013, 616–628.Google Scholar
Psiaki, M. and Humphreys, T. (2016) GNSS Spoofing and Detection. Proceedings of the IEEE, 104(6), 1258–1270.Google Scholar
Shirazaian, M. (2013). Incorporation of the GPS satellite ephemeris covariance matrix into the precise point positioning. Journal of Geodetic Sciences, 3(3), 143–150.Google Scholar
Teunissen, P.J.G. (2006) Testing theory; an introduction. 2nd edition, Delft VSSD, The Netherlands.Google Scholar
Teunissen, P.J.G. and Khodabandeh, A. (2015). Review and Principles of PPP-RTK Methods. Journal of Geodesy, 89, 217–240.Google Scholar
Tuka, A. and El-Mowafy, A. (2013). Performance Evaluation of Different Troposphere Delay Models and Mapping Functions. Measurement, 46(2): 928–937.Google Scholar