Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-22T20:11:35.017Z Has data issue: false hasContentIssue false

Performance Evaluation of the CNAV Broadcast Ephemeris

Published online by Cambridge University Press:  05 April 2019

Ahao Wang
Affiliation:
(College of Surveying and Geo-Informatics, Tong ji University, Shanghai 200092, China) (Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China)
Junping Chen*
Affiliation:
(Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China) (School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, China) (Shanghai Key Laboratory of Space Navigation and Positioning Techniques, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China)
Yize Zhang
Affiliation:
(Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China) (Tokyo University of Marine Science and Technology, Tokyo, 1358533, Japan)
Jiexian Wang
Affiliation:
(College of Surveying and Geo-Informatics, Tong ji University, Shanghai 200092, China)
Bin Wang
Affiliation:
(Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China)
*

Abstract

The new Global Positioning System (GPS) Civil Navigation Message (CNAV) has been transmitted by Block IIR-M and Block IIF satellites since April 2014, both on the L2C and L5 signals. Compared to the Legacy Navigation Message (LNAV), the CNAV message provides six additional parameters (two orbit parameters and four Inter-Signal Correction (ISC) parameters) for prospective civil users. Using the precise products of the International Global Navigation Satellite System Service (IGS), we evaluate the precision of satellite orbit, clock and ISCs of the CNAV. Additionally, the contribution of the six new parameters to GPS Single Point Positioning (SPP) is analysed using data from 22 selected Multi-Global Navigation Satellite System Experiment (MGEX) stations from a 30-day period. The results indicate that the CNAV/LNAV Signal-In-Space Range Error (SISRE) and orbit-only SISRE from January 2016 to March 2018 is of 0·5 m and 0·3 m respectively, which is improved in comparison with the results from an earlier period. The ISC precision of L1 Coarse/Acquisition (C/A) is better than 0·1 ns, and those of L2C and L5Q5 are about 0·4 ns. Remarkably, ISC correction has little effect on the single-frequency SPP for GPS users using civil signals (for example, L1C, L2C), whereas dual-frequency SPP with the consideration of ISCs results have an accuracy improvement of 18·6%, which is comparable with positioning accuracy based on an ionosphere-free combination of the L1P (Y) and L2P (Y) signals.

Type
Research Article
Copyright
Copyright © The Royal Institute of Navigation 2019 

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

Böhm, J., Möller, G., Schindelegger, M., Pain, G. and Weber, R. (2015). Development of an improved empirical model for slant delays in the troposphere (GPT2w). GPS Solutions, 19, 433441.10.1007/s10291-014-0403-7Google Scholar
Chang, Z.Q., Hu, X.G., Guo, R., Cao, Y.L., Wu, X.L., Wang, A.B. and Dong, E.Q. (2015). Comparison between CNMC and hatch filter & its precision analysis for BDS precise relative positioning. Scientia Sinica Physica, Mechanica & Astronomica, 45, 079508.Google Scholar
Cohenour, C. and Van Graas, F. (2011). GPS orbit and clock error distributions. Navigation. 58, 1728.10.1002/j.2161-4296.2011.tb01789.xGoogle Scholar
Creel, T., Dorsey, A.J., Mendicki, P.J., Little, J., Mach, R.G. and Renfro, B.A. (2007). Summary of accuracy improvements from the GPS legacy accuracy improvement initiative(L-AII). Proceedings of ION GNSS, 24812498.Google Scholar
Du, L., Liu, Z.J., Zhou, P.Y., Fang, S.C., Liu, L. and Ma, G.F. (2017). GEO NAV/CNAV-type broadcast ephemeris fitting without rotation of inclination. Acta Geodaetica et Cartographica Sinica, 46, 297306.Google Scholar
Feess, W., Cox, J., Howard, E. and Kovach, K. (2013). GPS inter-in-signal corrections (ISCs) study. In Proceedings of the 26th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS+ 2013), Nashville, TN, 951958.Google Scholar
Hatch, R.R. (1982). The synergism of GPS code and carrier measurements. Proceedings of the 3th International Geodetic Symposium on Satellite Doppler Positioning, New Mexico, 12131232.Google Scholar
Heng, L., Gao, G.X., Walter, T and Enge, P. (2011). Statistical characterization of GPS signal-in-space errors. Proceedings of ION ITM 2011, San Diego, CA, 312319.Google Scholar
Hofmann-Wellenhof, B., Lichtenegger, H. and Wasle, E. (2008). GNSS-Global Navigation Satellite Systems: GPS, GLONASS, Galileo, and more. Springer-Verlag Vienna.Google Scholar
IS-GPS-200H. (2014). Interface specification IS-GPS-200: navstar GPS space segment/navigation user segment interfaces. Technical Report Global Positioning System Directorate Systems Engineering & Integration. Available: http://www.gps.gov/technical/icwg/IS-GPS-200H.pdf.Google Scholar
IS-GPS-705D. (2014). Interface specification IS-GPS-705: navstar GPS space segment/user segment L5 interfaces. Technical Report Global Positioning System Directorate Systems Engineering & Integration. Available: http://www.gps.gov/technical/icwg/IS-GPS-705D.pdf.Google Scholar
Jee, G., Lee, H.B., Kim, Y.H., Chung, J.K. and Cho, J. (2010). Assessment of GPS global ionosphere maps (GIM) by comparison between CODE GIM and TOPEX/Jason TEC data: ionospheric perspective. Journal of Geophysical Research, 115, A10319.10.1029/2010JA015432Google Scholar
Montenbruck, O. and Hauschild, A. (2013). Code biases in multi-GNSS point positioning. In Proceedings of the 2013 International Technical Meeting of the Institute of Navigation, San Diego, CA, 616628.Google Scholar
Montenbruck, O., Hauschild, A. and Steigenberger, P. (2014). Differential code bias estimation using multi-GNSS observations and global ionosphere maps. Navigation, 61, 191201.10.1002/navi.64Google Scholar
Montenbruck, O., Langley, R.B. and Steigenberger, P. (2013). First live broadcast of GPS CNAV message. GPS World, 24, 14.Google Scholar
Montenbruck, O., Steigenberger, P. and Hauschild, A. (2015). Broadcast versus precise ephemerides: a multi-GNSS prespective. GPS solutions, 19, 321333.10.1007/s10291-014-0390-8Google Scholar
Montenbruck, O., Steigenberger, P. and Hauschild, A. (2018). Multi-GNSS signal-in-space range error assessment – methology and results. Advances in Space Research, 03, 041.Google Scholar
Petit, G. and Luzum, B. (2010). IERS Conventions. IERS Technical 2010 Note 36. Verlag des Bundesamts für Kartographie und Geodäsie, Frankfurt am Main, Germany. 2010.Google Scholar
Schaer, S. (2008). Differential code biases (DCB) in GNSS analysis. In Proceedings of IGS Workshop 2008, Miami Beach: Swiss Federal Office of Topography Swisstopo.Google Scholar
Schaer, S. and Werner, G. (1998). How to use IONEX. igscb.jpl.nasa.gov/igscb/data/format/ionex1.pdf.Google Scholar
Schmid, R., Steigenberger, P., Gendt, G., Ge, M. and Rothacher, M. (2007). Generation of a consistent absolute phase-center correction model for GPS receiver and satellite antennas. Journal of Geodesy, 81, 781798.10.1007/s00190-007-0148-yGoogle Scholar
Steigenberger, P., Montenbruck, O. and Hessels, U. (2015). Performance evaluation of the early CNAV navigation message. Proceedings of the 2015 International Technical Meeting of the Institute of Navigation, Dana Point, California, 155163.10.1002/navi.111Google Scholar
Wang, L.X., Huang, Z.G, and Zhao, Y. (2014). Navigation message designing with high accuracy for NAV. Chinese Journal of Aeronautics, 27, 9941001.10.1016/j.cja.2014.06.001Google Scholar
Wang, N.B., Yuan, Y.B., Li, Z.S., Montenbruck, O. and Tan, B.F. (2016b). Determination of differential code biases with multi-GNSS observations. Journal of Geodesy, 90, 209228.10.1007/s00190-015-0867-4Google Scholar
Wang, N.B., Yuan, Y.B., Zhang, B.C. and Li, Z.S. (2016a). Accuracy evaluation of GPS broadcast Inter-signal Correction(ISC) parameters and their impacts on GPS standard positioning. Acta Geodaetica et Cartographica Sinica, 45, 919928.Google Scholar
Warren, D.L. and Raquet, J.F. (2003). Broadcast vs. precise GPS ephemerides: a historical perspective. GPS Solutions, 7, 151156.10.1007/s10291-003-0065-3Google Scholar
Yin, H., Morton, Y., Carroll, M. and Vinande, E. (2014). Performance analysis of L2 and L5 CNAV broadcast ephemeris for orbit calculation. In Proceedings of the 2014 International Technical Meeting of the Institute of Navigation, San Diego, CA, 761768.Google Scholar
Zhang, Y.Z., Chen, J.P., Zhou, J.H., Yang, S.N., Wang, B., Chen, Q. and Gong, X.Q. (2016). Analysis and Application of BDS broadcast ephemeris Bias. Acta Geodaetica et Cartographica Sinica, 45, 6471.Google Scholar