Assessment of Pseudorange Multipath at Continuous GPS Stations in Mexico


We conducted a study to quantify the amount of pseudorange multipath at continuous Global Positioning System (CGPS) stations in the Mexican territory. These CGPS stations serve as reference stations enabling rapid high-precision three-dimensional positioning capabilities, supporting a number of commercial and public safety applications. We studied CGPS data from a large number of publicly available networks spanning Mexico. These include the RGNA (National Active Geodetic Network) administered by INEGI (National Institute of Statistics and Geography), the PBO network (Plate Boundary Observatory) funded by the National Science Foundation (NSF) and operated by UNAVCO (University NAVstar Consortium), the Southern California Integrated GPS Network (SCIGN), which is a collaboration effort of the United States Geological Survey (USGS), Scripps Institution of Oceanography and the Jet Propulsion Laboratory (JPL), the UNAM network, operated by the National Seismological System (SSN) and the Institute of Geophysics of the National Autonomous University of Mexico (UNAM), the Suominet Geodetic Network (SNG) and the CORS (Continuously Operating Reference Station) network, operated by the Federal Aviation Administration (FAA). We evaluated a total of 53 CGPS stations, where dual-frequency geodetic-grade receivers collected GPS data continuously during the period from 1994 to 2012. Despite carefully selected locations, all GPS stations are, to some extent, affected by the presence of signal multipath. For GPS network users that rely on pseudorange observables, the existence of pseudorange multipath could be a critical source of error depending on the time scale of the application. Thus, to identify the most and the least affected GPS stations, we analyzed the averaged daily root mean square pseudorange multipath variations (MP1-RMS and MP2-RMS) for all feasible satellites tracked by the CGPS networks. We investigated the sources of multipath, including changes associated with hardware replacement (i.e., receiver and antenna type) and receiver firmware upgrades.

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G. Vázquez, R. Bennett and J. Spinler, "Assessment of Pseudorange Multipath at Continuous GPS Stations in Mexico," Positioning, Vol. 4 No. 3, 2013, pp. 253-265. doi: 10.4236/pos.2013.43025.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] A. Bilich and K. M. Larson, “Mapping the GPS Multipath Environment Using the Signalto-Noise Ratio (SNR),” Radio Science, Vol. 42, No. 6, 2007, pp. 1-16. doi:10.1029/2007RS003652
[2] P. Elósegui, J. L. Davis, R. K. Jaldehag, J. M. Johansson, A. E. Niell and I. I. Shapiro, “Geodesy Using the Global Positioning System: The Effects of Signal Scattering on Estimates of Site Position,” Journal of Geophysical Research: Solid Earth, Vol. 100, No. B6, 1995, pp. 9921-9934. doi:10.1029/95JB00868
[3] L. Estey and C. M. Meertens, “TEQC: The Multi-Purpose Toolkit for GPS/GLONASS Data,” GPS Solutions, Vol. 3, No. 1, 1999, pp. 42-49. doi:10.1007/PL00012778
[4] L. L. Ge, S. W. Han and C. Rizos, “Multipath Mitigation of Continuous GPS Measurements Using an Adaptive Filter,” GPS Solutions, Vol. 4, No. 2, 2000, pp. 19-30. doi:10.1007/PL00012838
[5] L. L. Ge, S. W. Han and C. Rizos, “GPS Multipath Change Detection in Permanent GPS Stations,” Survey Review, Vol. 36, No. 283, 2002, pp. 306-322. doi:10.1179/003962602791483271
[6] S. Hilla and M. Cline, “Evaluating Pseudorange Multi-path Effects at Stations in the National CORS Network,” GPS Solutions, Vol. 8, No. 4, 2004, pp. 253-267. doi:10.1007/s10291-003-0073-3
[7] M. A. King and C. S. Watson, “Long GPS Coordinate Time Series: Multipath and Geometry Effects,” Journal of Geophysical Research: Solid Earth, Vol. 115, No. B4, 2010. doi:10.1029/2009JB006543
[8] K. M. Larson, E. Gutmann, V. Zavorotny, J. Braun, M. Williams and F. Nievinski, “Can We Measure Snow Depth with GPS Receivers?” Geophysical Research Letters, Vol. 36, No. 17, 2009, pp. 1-5. doi:10.1029/2009GL039430
[9] A. R. Lowry, K. M. Larson, V. Kostoglodov and R. Bilham, “Tansient Fault Slip in Guerrero, Southern Mexico,” Geophysical Research Letters, Vol. 28, No. 19, 2001, pp. 3753-3756. doi:10.1029/2001GL013238
[10] K. D. Park, P. Elósegui, J. L. Davis, P. O. J. Jarlemark, B. E. Corey, A. E. Niell, J. E. Normandeau, C. E. Meertens, and V. A. Andreatta, “Development of an Antenna and Multipath Calibration System for Global Positioning System Sites,” Radio Science, Vol. 39, No. 5, 2004, pp. 1-13. doi:10.1029/2003RS002999
[11] R. Jim, “Systematic Errors in GPS Position Estimates,” IGS Workshop 2006, Darmstadt, 8-11 May 2006.
[12] C. Rizos and S. W. Han, “Quality Control Issues in Real-time GPS Positioning,” IUGG Congress, Birmingham, 18-30 July 1999.
[13] G. W. Roberts, X. Meng, A. H. Dodson and E. Cosser, “Multipath Mitigation for Bridge Deformation Monitoring,” Journal of Global Positioning System, Vol. 1, No. 1, 2002, pp. 25-33. doi:10.5081/jgps.1.1.25
[14] C. Satirapod, R. Khoonphool and C. Rizos, “Multipath Mitigation of Permanent GPS Stations Using Wavelets,” International Symposium on GPS/GNSS, Tokyo, 15-18 November 2003, pp. 133-139.
[15] E. E. Small, K. M. Larson and J. J. Braun, “Sensing Vegetation Growth with Reflected GPS Signals,” Geophysical Research Letters, Vol. 37, No. , 2010, pp. 1-5. doi:10.1029/2010GL042951
[16] G. E. Vázquez and D. A. Grejner-Brzeziska, “A Case Study for Pseudorange Multipath Estimation and Analysis: TAMDEF GPS Network,” Geofísica Internacional, Vol. 51, No. 1, 2012, pp. 63-72.
[17] S. Yoshioka, T. Mikumo, V. Kostoglodov, K. M. Larson, A. R. Lowry and S. K. Singh, “Interplate Coupling and a Recent Aseismic Slow Slip Event in the Guerrero Seismic Gap of the Mexican Subduction Zone, as Deduced from GPS Data Inversion Using a Bayesian Information Criterion,” Physics of the Earth and Planetary Interiors, Vol. 146, No. 3-4, 2004, pp. 513-530. doi:10.1016/j.pepi.2004.05.006
[19] UNAVCO, “QC v3 User Guide,” 1994.

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