Performance analysis of ambiguity resolution on PPP and relative positioning techniques: consideration of satellite geometry

Ambiguity resolution plays an important role in surveying using Precise Point Positioning (PPP) and relative positioning techniques that require high accuracy. In this study, ambiguity resolution performance of PPP and relative positioning under the unobstructed (with 7° cut-off angle) and constrained environment (with 25° cut-off angle, such as nearby buildings and street-canyons) using final/ultra-rapid orbit and clock products are investigated for different observation time. Seventeen globally distributed stations and six baselines of lengths from 270 km to 2100 km are chosen for conducting PPP and relative positioning, respectively. A 31-day period in January 2018 is chosen for processing using 24-, 12-, 6-, 4-, 2- and 1-h observations. The results indicate that sub-mm to cm levels of improvement in horizontal and vertical coordinate components are generally observed with ambiguity resolution for PPP and relative positioning techniques compared to the float counterparts. Moreover, accuracy degradation of ambiguity resolution compared to float solution is observed generally in the vertical component using the 25° elevation cut-off angle for both techniques. As the observation time increases, the accuracy improvements from ambiguity resolution decrease for each technique. In addition, fixing to the wrong integer ambiguities are generally seen with a short observation time and a 25° elevation cut-off angle for both techniques due to the poor satellite geometry. As far as baseline length in relative technique is concerned, the testing results show that there is no direct relation between baseline length and the accuracy improvement from ambiguity resolution compared to the float solution. The results also reveal that the coordinates obtained from ambiguity resolution does not significantly change in the relative technique using final or ultra-rapid orbit/clock products, whereas the changes in PPP are significant for most of the stations.

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  • Alcay, S., Ogutcu, S., Kalayci, I and Yigit, C.O. (2019). Displacement monitoring performance of relative positioning and Precise Point Positioning (PPP) methods using simulation apparatus, Advances in Space Research 63, 5, 1697–1707.
  • Bar‐Sever, Y. E., Kroger, P. M., and Borjesson, J. A. (1998). Estimating horizontal gradients of troposphericpath delay with a single GPS receiver. Journal of Geophysical Research: Solid Earth, 103(B3), 5019-5035.
  • Blewitt G., Young LE., and Meehan TH. (1989). Subcentimeter baselines within seconds using ROGUE receivers: introducing the rapid static survey (RSS) method. In: International association of geodesy conference, Edinburgh, August, 1989.
  • Bezcioglu M., Yigit, O. C and El-Mowafy, A. (2019). Kinematic PPP-AR in Antarctic: Comparing Methods for Precise Positioning. Sea Technology.
  • Bertiger, W., Desai, S. D., Haines, B., Harvey, N., Moore, A. W., Owen, S and Weiss, J. P. (2010). Single receiver phase ambiguity resolution with GPS data. Journal of Geodesy, 84(5), 327-337.
  • Brach, M and Zasada, M. (2014). The effect of mounting height on GNSS receiver positioning accuracy in forest conditions. Croatian Journal of Forest Engineering: Journal for Theory and Application of Forestry Engineering, 35(2), 245-253.
  • Chen, H., Xiao, Y., Jiang, W., Zhou, X and Liu, H. (2017). An improved method for multi-GNSS baseline processing using single difference. Advances in Space Research.
  • Choy, S., Bisnath, S and Rizos, C. (2017). Uncovering common misconceptions in GNSS Precise Point Positioning and its future prospect. GPS solutions, 21(1), 13-22.
  • Gandolfi, S., Tavasci, L and Poluzzi, L. (2017). Study on GPS–PPP precision for short observation sessions. GPS Solutions, 21(3), 887-896.
  • Ge, M., Gendt, G., Rothacher, M. A., Shi, C and Liu, J. (2008). Resolution of GPS carrier-phase ambiguities in precise point positioning (PPP) with daily observations. Journal of Geodesy, 82(7), 389-399.
  • Geng, J., Teferle, F. N., Shi, C., Meng, X., Dodson, A. H and Liu, J. (2009). Ambiguity resolution in precise point positioning with hourly data. GPS solutions, 13(4), 263- 270.
  • Geng, J., Jiang, P and Liu, J. (2017). Integrating GPS with GLONASS for high‐rate seismogeodesy. Geophysical research letters, 44(7), 3139-3146.
  • Goudarzi, M. A and Banville, S. (2018). Application of PPP with ambiguity resolution in earth surface deformation studies: a case study in eastern Canada. Survey Review, 50(363), 531-544.
  • Joosten, P. (2000). Fixing the ambiguities-are you sure they're right?. GPS world, 11(5), 46-51.
  • Lagler, K., Schindelegger, M., Böhm, J., Krásná, H and Nilsson, T. (2013). GPT2: Empirical slant delay model for radio space geodetic techniques. Geophysical research letters, 40(6), 1069-1073.
  • Li, X., Ge, M., Zhang, X., Zhang, Y., Guo, B., Wang, R ... and Wickert, J. (2013). Real‐time high‐rate co‐seismic displacement from ambiguity ‐ fixed precise point positioning: Application to earthquake early warning. Geophysical Research Letters, 40(2), 295-300.
  • Li, P., Zhang, X., Ren, X., Zuo, X and Pan, Y. (2016). Generating GPS satellite fractional cycle bias for ambiguity-fixed precise point positioning. GPS solutions, 20(4), 771-782.
  • Li, X., Chen, X., Ge, M and Schuh, H. (2018). Improving multi-GNSS ultra-rapid orbit determination for real-time precise point positioning. Journal of Geodesy, 1-20.
  • Li, X., Li, X., Liu, G., Feng, G., Guo, F., Yuan, Y and Zhang, K. (2018). Spatial–temporal characteristic of BDS phase delays and PPP ambiguity resolution with GEO/IGSO/MEO satellites. GPS Solutions, 22(4), 123.
  • Pan, L., Cai, C., Santerre, R and Zhu, J. (2014). Combined GPS/GLONASS precise point positioning with fixed GPS ambiguities. Sensors, 14(9), 17530-17547.
  • Pehlivan, H., Bezcioğlu, M and Yılmaz, M. (2019). PERFORMANCE OF NETWORK RTK CORRECTION TECHNIQUES (FKP, MAC and VRS) UNDER LIMITED SKY VIEW CONDITION. International Journal of Engineering and Geosciences, 4(3), 106-114.
  • Petit, G.; Luzum, B. IERS Conventions (2010). Bureau International des Poids et Mesures Sevres (France), 2010. Available online: https://www.iers.org/IERS/EN/Publications/TechnicalNotes/tn36.html (accessed on 1 July 2018).
  • Teunissen, P. J. G and Khodabandeh, A. (2015). Review and principles of PPP-RTK methods. Journal of Geodesy, 89(3), 217-240.
  • Teunissen, P and Montenbruck, O. (Eds.). (2017). Springer handbook of global navigation satellite systems. Springer.
  • Tusat, E and Ozyuksel, F. (2018). Comparison of GPS satellite coordinates computed from broadcast and IGS final ephemerides. International Journal of Engineering and Geosciences, 3(1), 12-19.
  • Schwarz, C. R., Snay, R. A and Soler, T. (2009). Accuracy assessment of the National Geodetic Survey’s OPUS-RS utility. GPS solutions, 13(2), 119-132.
  • Shi, C., Lou, Y. D., Zhang, H. P., Zhao, Q., Geng, J., Wang, R. ... and Liu, J. (2010). Seismic deformation of the Mw 8.0 Wenchuan earthquake from high-rate GPS observations. Advances in Space Research, 46(2), 228-235.
  • Wielgosz, P. (2011). Quality assessment of GPS rapid static positioning with weighted ionospheric parameters in generalized least squares. GPS solutions, 15(2), 89-99.
  • Wu, J. T., Wu, S. C., Hajj, G. A., Bertiger, W. I and Lichten, S. M. (1992, August). Effects of antenna orientation on GPS carrier phase. In Astrodynamics 1991 (pp. 1647-1660).
  • Xiao, G., Li, P., Sui, L., Heck, B and Schuh, H. (2019). Estimating and assessing Galileo satellite fractional cycle bias for PPP ambiguity resolution. GPS Solutions, 23(1), 3.
  • Yigit C.O, Gikas V., Alcay S and Ceylan A. (2014) Performance evaluation of short to long term GPS, GLONASS and GPS/GLONASS post-processed PPP, Survey Review, 46(3), 155-166.
  • Zumberge, J. F., Heflin, M. B., Jefferson, D. C., Watkins, M. M and Webb, F. H. (1997). Precise point positioning for the efficient and robust analysis of GPS data from large networks. Journal of geophysical research: solid earth, 102(B3), 5005-5017.