The positioning accuracy of single frequency precise point positioning (SFPPP) attributes mainly to the ionosphere error, which strongly affects GNSS signals. When GNSS signals pass through the various ionosphere layers, they will be bent and their speed will be changed due to dispersive nature of ionosphere. To correct the ionosphere error, it is common to use Klobuchar ionosphere model or Global Ionosphere Maps (GIM). However, Klobuchar can deal with only about 50% of the Ionosphere effect and global Ionosphere maps are often inadequate to describe detailed features of local ionosphere because of limited precision and resolution. In this paper, an enhanced local ionosphere model was developed relying on modeling of measurements from a dense Egyptian permanent tracking GNSS network in order to achieve high precision ionosphere delay correction. The performance of the developed enhanced Egyptian ionosphere model (EIM) was verified through multi-constellations SFPPP accuracy for static and kinematic modes. For static mode, 24 hours multi-constellations datasets collected at three selected stations, Alexandria, Cairo, and Aswan, in Egypt on February 27, 2017, to investigate the performance of the developed local ionospheric model in comparison with the Klobuchar, GIM and ionosphere free models. After session time of half an hour, the results show that the performance of static SFPPP based on the developed Egyptian ionospheric map (EIM) achieved a comparable accuracy WRT using ionosphere free model. While using EIM, achieved an improvements of (38%, 28%, and 42%) and (32%, 10%, and 37%) for accuracy of latitude, longitude, and altitude in comparison with using Klobuchar and GIM models, respectively For kinematic mode, datasets of 2 hours of observations with 1 second sampling rate were logged during vehicular test; the test was carried out on the ring road of the city of Cairo, Egypt, on September 16, 2017. After half an hour of kinematic SFPPP data-processing, the performance of using Egyptian ionospheric map (EIM) for ionosphere delay correction, achieved an improvements of three dimension coordinates of (83%, 47%, and 62%) and (57%, 65%, and 21%) with respect to using Klobuchar model and GIM model, respectively.
If the inline PDF is not rendering correctly, you can download the PDF file here.
Abd Rabbou.M.& El-Rabbany. A. (2015) “Multi-Constellation GNSS Single frequency PPP: An Efficient Technique for Low Cost Surveying Applications”. Research poster The Association of Ontario Land Surveyors Huntsville Canada. 26-28th February2015.
Beran T. (2008) “Single-frequency Single-receiver Terrestrial and Space-borne Point Positioning”. PhD thesis University of New Brunswick Frederiction New Brunswick Canada
Bock H. Jäggi A. Dach R. Schaer S. and Beutler G. (2009). “GPS single-frequency orbit determination for low earth orbiting satellites”. Advances in Space Research 43(5) 783-791.
Chen K. and Gao Y. (2005). “Real-time precise point positioning using single frequency data”. Proceedings of ION GNSS 2005 13-16 Sep 2005 Long Beach California USA 1514-1523. Georgia USA 2400-2414.
Fei Guo Xingxing Li Xiaohong Zhang Jinling Wang (2016) “The contribution of Multi-GNSS Experiment (MGEX) to precise point positioning”. Advances in Space Research 59 (2017) 2714-2725
Gao Y. Zhang Y. and Chen K. (2006). “Development of a real-time single-frequency precise point positioning system and test results”. Proceedings of ION GNSS 2006 26-29 Sep 2006 Fort Worth Texas USA 2297-2303.
Hernández-Pajares et al. (2009) “The IGS VTEC maps: a reliable source of ionospheric information since 1998”. Journal of Geodesy Volume 83 Issue 3-4 PP 263-275 March 2009. https://doi.org/10.1007/s00190-008-0266-1
Héroux P. Y. Gao J. Kouba F. Lahaye Y.Mireault P. Collins K. Macleod P. Tétreault and K. Chen (2004). “Products and Applications for Precise Point Positioning - Moving Towards Real-Time”. Proceedings of the 17th International Technical Meeting of the Satellite Division of the Institute of Navigation ION GNSS 2004 Long Beach CA September 21-24 2004 1832-1843.
Hofmann-Wellenhof B. Lichtenegger H. and Wasle E. (2008). “GNSS - Global Navigation Satellite Systems”. Springer-Verlag Wien.
Klobuchar J. A. (1987). “Ionospheric time-delay algorithm for single-frequency GPS users”. IEEE Transactions on Aerospace and Electronic Systems 23(3) 325-331 doi:
Klobuchar, J. A. (1987). “Ionospheric time-delay algorithm for single-frequency GPS users”. IEEE Transactions on Aerospace and Electronic Systems, 23(3), 325-331, doi: 10.1109/TAES.1987.310829.)| false
Leandro R. Langley R. Santos M.(2008). “UNB3m_pack: A neutral atmosphere delay package for radiometric space techniques”. GPS Solut. 2008;12:65-70.
Montenbruck O Hauschild A Steigenberger P (2014). “Differential Code Bias Estimation Using Multi-GNSS Observations and Global Ionosphere Maps”. Navigation 61(3) 191-201.
Montenbruck O Steigenberger P Khachikyan R Weber G Langley R.B Mervart L Hugentobler U (2014). “IGS-MGEX: Preparing the Ground for Multi-Constellation GNSS Science”. 4th Int. Colloquium on Scientific and Fundamental Aspects of the Galileo System Prague 4-6 Dec 2013
Mostafa RABAH et al (2018). “Evaluation of the IGS-Global Ionospheric Mapping model over Egypt”. journal Annales Geophysicae. https://doi.org/10.5194/angeo-2018-92
Odijk D. Teunissen P. J. G. and Zhang B. (2012). “Single-frequency integer ambiguity resolution enabled precise point positioning”. Journal of Surveying Engineering doi:
Odijk, D., Teunissen, P. J. G. and Zhang, B. (2012). “Single-frequency integer ambiguity resolution enabled precise point positioning”. Journal of Surveying Engineering, doi: 10.1061/(ASCE)SU.1943-5428.0000085.)| false
Roma David & Pajares Manuel & Krankowski Andrzej & Kotulak Kacper & Ghoddousi-Fard Reza & Yuan Yunbin & Li Zishen & Zhang Hongping & Shi Chuang & Wang Cheng & Feltens Joachim & Vergados Panagiotis & Komjathy Attila & Schaer Stefan & García-Rigo Alberto & Gómez Cama José María. (2017) “Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle”. Journal of Geodesy. 10.1007/s00190-017-1088-9.
Schaer S. Gurtner W. Feltens J.(1998) "IONEX: The Ionosphere Map Exchange Format Version 1" Proceedings of the IGS AC Workshop Darmstadt Germany 9.-11.
Schaer S. G. Beutler L. Mervart M. Rothacher and U. Wild (1995) "Global and Regional Ionosphere Models Using the GPS Double Difference Phase Observable" in IGS Workshop Proceedings on Special Topics and New Directions edited by G. Gendt and G. Dick pp. 77-92 GFZ Potsdam Germany May 15-18 1995.
Seeber G. (2003) “Satellite Geodesy”. 2nd Edition de Gruyter Berlin Germany
Simsky A. (2006) “Standalone Real-Time Navigation Algorithm for Single-Frequency Ionosphere-Free Positioning Based on Dynamic Ambiguities (DARTS-SF)”. Proceedings of ION GNSS 18th International Technical Meeting of the Satellite Division Fort Worth Texas 301-308
Van Bree R. J. P. and Tiberius C. C. J. M. (2011). “Real-time single-frequency precise point positioning: accuracy assessment”. GPS Solutions doi: