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Single Frequency WAAS Augmentation Observations (L1 vs. L5) on a Ground Based GPS L1 C/A Solution

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DOI: 10.4236/pos.2014.53010    4,463 Downloads   5,213 Views   Citations

ABSTRACT

This paper presents observations on the WAAS L1 and L5 signals quality and their impact on the robustness of the navigation solution by quantifying the contributions of each broadcasted differential correction. This work is undertaken with the intent of defining performance benefits of L5 by dual frequency WAAS users and is to provide useful material for Minimum Operational Performance Standard (MOPS) development. In this perspective, a study of the WAAS signal characteristics is first carried out. The information gathered is then used to compare various GPS solutions in terms of frequency diversity, satellite diversity, pseudorange noise and different signal corrections and their impacts. These solutions are compared against a reference standalone GPS solution. All statistics are computed with respect to a post-processed Novatel Waypoint Real-Time Kinematics (RTK) GPS L1/L2 semi-codeless static solution, considered as the reference. A discussion on some simplifications with respect to specifications (i.e. MOPS) that could be considered by receiver manufacturers closes the paper. It is confirmed that the current WAAS navigation message definition is the same on both the L1 and L5 frequencies, the latter further being Manchester coded, thus avoiding data ambiguity. The +5 dB SNR on L5 has minor impacts in terms of reliability and continuous availability in the presented scenarios, but would become especially beneficial in hostile environments, despite a greater number of pulsed interferers. Another demonstration is that the WAAS message varies slightly from one WAAS satellite to another, even if corrections are generated centrally. Finally, it is observed that WAAS and GPS signals pseudorange noise are comparable on a “per frequency” basis.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

Fortin, M. , Guay, J. and Landry, R. (2014) Single Frequency WAAS Augmentation Observations (L1 vs. L5) on a Ground Based GPS L1 C/A Solution. Positioning, 5, 70-83. doi: 10.4236/pos.2014.53010.

References

[1] Braff, R. and Shively, C. (1986) GPS Integrity Channel. Navigation, Journal of the Institute of Navigation, 32, 334-350.
https://ion.org/publications/abstract.cfm?articleID=100431
[2] Kim, E., Walter, T. and Powell, J.D. (2006) Optimizing WAAS Accuracy/Stability for a Single Frequency Receiver. Proceedings of the 19th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2006), Fort Worth, September 2006, 962-970.
[3] National Coordination Office for Space-Based Positioning Navigation and Timing (2012) Selective Availability.
http://www.gps.gov/systems/gps/modernization/sa/
[4] Walter, T., Blanch, J., Phelts, R.E. and Enge, P. (2012) Evolving WAAS to Serve L1/L5 Users. Navigation, 59, 317-327. http://dx.doi.org/10.1002/navi.21
[5] RTCA (2006) Minimum Operational Performance Standards for Global Positioning System/Wide Area Augmentation System Airborne Equipment. Document Number: DO-229D.
[6] Lawrence, D., Bunce, D., Mathur, N.G. and Sigler, C.E. (2007) Wide Area Augmentation System (WAAS)—Program Status. Proceedings of the 20th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2007), The Institute of Navigation, 892-899.
[7] Hathaway, D.H. (2012) The Sunspot Cycle. http://solarscience.msfc.nasa.gov/SunspotCycle.shtml
[8] Gannon, M. (2013) Sun’s 2013 Solar Activity Peak Is Weakest in 100 Years. Online.
http://www.space.com/21937-sun-solar-weather-peak-is-weak.html
[9] Federal Aviation Administration (2012). Navigation Services—WAAS—News.
http://www.faa.gov/about/office_org/headquarters_offices/ato/serv
ice_units/techops/navservices/gnss/waas/news/
[10] Fernandez-Prades, C., Presti, L.L. and Falletti, E. (2011) Satellite Radio Localization from GPS to GNSS and Beyond: Novel Technologies and Applications for Civil Mass Market. Proceedings of the IEEE, 99, 1882-1904.
http://dx.doi.org/10.1109/JPROC.2011.2158032
[11] Jan, S.-S. (2002) Analysis of a Three-Frequency GPS/WAAS Receiver to Land an Airplane. Proceedings of the 15th International Technical Meeting of the Satellite Division of the Institute of Navigation ION GPS 2002, Oregon Convention Center, Portland, 24-27 September, 2002, 2576-2586.
[12] Murfin, T. (2012) ION Nashville 2012 Round-Up. GPS World.
http://www.gpsworld.com/ion-nashville-2012-round-up/
[13] Rho, H. and Langley, R.B. (2008) Evaluation of the New WAAS L5 Signal. Proceedings of ION GNSS 21st International Technical Meeting of the Satellite Division of the Institute of Navigation, Savannah, 16-19 September 2008, 1667-1678.
[14] Hsu, P.-H., Cheung, L. and Grewal, M. (2004) Prototype Test Results of L1/L5 Signals of Future GEO Satellites. Proceedings of ION GNSS 17th International Technical Meeting of the Satellite Division, Long Beach, 21-24 September, 1359-1366.
[15] Federal Aviation Administration (2011) WAAS Technical Specifications for GEO 5/6/7 Service Lease. Department of Transportation, Vol. WAAS100232, 45.
[16] Chen, Y.H., Juang, J.C., De Lorenzo, D.S., Seo, J., Lo, S., Enge, P., et al. (2011) Real-Time Dual-Frequency (L1/L5) GPS/WAAS Software Receiver. Proceedings of the 24th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2011), Oregon Convention Center, Portland, Oregon, 20-23 September 2011, 767-774.
[17] Federal Aviation Administration (2008) Global Positionning System Wide Area Augmentation System (WAAS) Performance Standard. 1st Edition, Department of Transportation, 28.
http://www.gps.gov/technical/ps/2008-WAAS-performance-standard.pdf
[18] Landry, R.J., Fortin, M.A. and Guay, J.C. (2010) Universal Acquisition and Tracking Apparatus for Global Navigation Satellite System (GNSS). Canada Patent No 12/767,773.
[19] Fortin, M.A., Guay, J.C. and Landry, R.J. (2009) Development of a Universal GNSS Tracking Channel. Proceedings of the 22nd International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2009, Savannah, GA, 22-25 September 2009, 259-272.
[20] Fortin, M.A., Guay, J.C. and Landry, R.J. (2009) Real-Time Low-Cost Multipath Mitigation Technique Calibrated through Real Data Repeatable Testing. Proceedings of the 22nd International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2009, Savannah, Georgia, 22-25 September 2009, 2316-2328.
[21] Guay, J.C., Sauriol, B. and Fortin, M.A. (2008) Real-Time Multipath Monitoring and Characterization with a Variable Spacing Correlator on a FPGA-Based Software GNSS Receiver. Proceedings of the 21st International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2008, Savannah, 16-19 September 2008, 2332- 2342.
[22] Sauriol, B. and Landry, R.J. (2007) FPGA-Based Architecture for High Throughput, Flexible and Compact Real-Time GNSS Software Defined Receiver. Proceedings of the 2007 National Technical Meeting of the Institute of Navigation, San Diego, 22-24 January 2007, 708-717.
[23] Radio Technical Commission for Aeronautics Special Committee 159 (2001) Minimum Operational Performance Standards for Global Positioning System/Wide Area Augmentation System Airborne Equipment. RTCA.
http://www.rtca.org/store_product.asp?prodid=817
[24] Langley, R.B. and Rho, H. (2009) Innovation: The WAAS L5 Signal. GPS World.
http://www.gpsworld.com/gnss-system/innovation-the-waas-l5-signal-7047
[25] Issler, J.L., Ries, L., Bourgeade, J.M., Lestarquit, L. and Macabiau, C. (2004) Probabilistic Approach of Frequency Diversity as Interference Mitigation Means. Proceedings of the 17th International Technical Meeting of the Satellite Division of the Institute of Navigation (ION GNSS 2004), Long Beach, CA, 21-24 September 2004, 2136-2145.
[26] Guay, J.C. (2010) Récepteur SBAS-GNSS logiciel pour des applications temps-réel. école de technologie supérieure, Montréal.
[27] Todd, K.M. (2005) Error Correction Coding: Mathematical Methods and Algorithms. Wiley Series Edition, John Wiley & Sons Inc., New Jersey. ISBN: 978-0-471-64800-0.
[28] Federal Aviation Administration (2001) Specification for the Wide Area Augmentation System (WAAS). Department of Transportation, 156.
http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/
techops/navservices/gnss/library/documents/media/waas/2892bC2a.pdf
[29] Julien, O., Macabiau, C., Issler, J.L., Nouvel, O. and Vigneau, W. (2006) Analysis and Quality Study of GNSS Monitoring Ground Stations’ Pseudorange and Carrier-Phase Measurements. Proceedings of the 19th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2006), Fort Worth Convention Center, Fort Worth, TX, 26-29 September 2006, 971-980.
[30] Betz, J.W. (2000) Design and Performance of Code Tracking for the GPS M Code Signal. Proceedings of the 13th International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2000, Salt Lake City, UT, 19-22 September 2000, 2140-2150.
[31] Ries, L., Lestarquit, L., Armengou-Miret, E., Legrand, F., Vigneau, W., Bourga, C., Erhard, P. and Issler, J.L. (2002) A Software Simulation Tool for GNSS2 BOC Signals Analysis. Proceedings of the 15th International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2002, Institute of Navigation, Portland, OR, 24-27 September 2002, 2225-2239.
[32] ARINC Engineering Services (2005) Navstar GPS Space Segment/User Segment L5 Interfaces. Interface Specification, Navstar GPS Joint Program Office, El Segundo, California, 95.
[33] Global Positioning System Wing (GPSW) Systems Engineering & Integration (2010) Navstar GPS Space Segment/ Navigation User Interfaces. Los Angeles Air Force Base, El Segundo, California, 185.
http://www.losangeles.af.mil/shared/media/document/AFD-100813-045.pdf
[34] Federal Aviation Administration (2012) Satellite Position and WAAS Status.
http://www.nstb.tc.faa.gov/RT_WaasSatelliteStatus.htm
[35] Oolman, L. (2012) Surface Observations. http://weather.uwyo.edu/surface/meteorogram/
[36] El-Rabbany, A. (2002) Introduction to GPS: The Global Positoning System. Mobile communications Series, Boston.
[37] Jan, S.S. (2003) Aircraft Landing Using a Modernized Global Positioning System and the Wide Area Augmentation System. Doctor of Philosophy Thesis, Aeronautics and Astronautics, Stanford University, Stanford.
[38] Van Dierendonck, A.J., Hegarty, C., Niles, R., Morrissey, T. and Reddan, P. (2005) Next Generation Satellite Based Augmentation System (SBAS) Signal Specification. Proceedings of the 2005 National Technical Meeting of the Institute of Navigation, San Diego, CA, 24-26 January 2005, 371-384.
[39] Schempp, T., Burke, J. and Rubin, A. (2008) WAAS Benefits of GEO Ranging. 21st International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2008, Savannah, GA, 16-19 September 2008, 2000-2007.

  
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