Farklı GNSS sistemlerinin etkileri üzerine istatistiksel bir araştırma

Öz

Bu çalışma, Magic GNSS yazılımı kullanılarak farklı GNSS günlerinde farklı yükseklik açıları altında yalnızca GPS, yalnızca GLONASS ve kombine GPS/GLONASS gözlemlerinin çeşitli çözümlerinin etkilerini araştırmak içindir. Uydu sayısının artan veya azalan ölçüm doğruluğu üzerindeki etkilerini araştırmak için farklı yükseklik açıları ve ölçüm günleri dikkate alınmıştır. Değerlendirme, ANOVA ve Post Hoc gibi istatistiksel testlere dayanmaktadır. Çalışmanın amaçlarını gerçekleştirmek için İSKİ CORS ağının İstanbul ilindeki tüm sürekli istasyonlarından oluşan bir test ağı kullanılmıştır. Sonuçlar, GNSS ile çeşitli yükseklik açılarında ve farklı uydu konfigürasyonlarında elde edilen noktaların konumları arasında önemli farklılıklar olduğunu göstermiştir. Farklı uydu ve ölçme konfigürasyonları, konum doğruluğunu etkilemektedir. Ayrıca sonuçlar, 136. GNSS gününde X ve Z bileşenlerinde anlamlı farklılıklar bulunduğunu, Y bileşenlerinde ise anlamlı bir farkla karşılaşılmadığını göstermiştir. Sonuç olarak, kombine GPS/GLONASS çözümleri, yalnızca GPS çözümlerine ve yalnızca GLONASS gözlemlerine göre 5° 10° veya 15°'lik küçük yükseklik açıları altında daha iyi sonuçlar vermiştir.

Anahtar Kelimeler

• ANOVA
• Yükseklik Açıları
• GPS/GLONASS
• Magic GNSS
• Post Hoc Testi

A statistical investigation on the effects of different GNSS systems

Öz

This study is to investigate the effects of various solutions of GPS only, GLONASS only, and combined GPS/GLONASS observations under different elevation angles on different GNSS days by using Magic GNSS software. Different elevation angles and measurement days were considered to investigate the increasing or decreasing number of satellites’ effects on the measurement accuracy, and positioning accuracy affected by the solutions of GPS only, GLONASS only, and combined GPS/GLONASS observations, respectively. The assessment was based on statistical tests, namely ANOVA and Post Hoc tests. A test network, consisting of all the continuous stations of the ISKI CORS network in Istanbul city, was used to fulfill the aims of the study. The results showed that significant differences between positions of points obtained by GNSS in various elevation angles and with different satellite configurations were determined. Different satellite and measurement configurations affect position accuracy. In addition, the results showed that on the 136th GNSS day, significant differences in X and Z components were found while in Y components there were no significant differences encountered. In conclusion, combined GPS/GLONASS solutions produced better results under small elevation angles of 5° 10° or 15° than the solutions of GPS-only and GLONASS-only observations.

Anahtar Kelimeler

• ANOVA
• Elevation Angles
• GPS/GLONASS
• magic GNSS
• Post Hoc Test

Kaynakça

1. M. P. Stewart, M. Tsakiri, J. Wang and J. F. Monico, The contribution of GLONASS measurements to regional and continental scale geodetic monitoring regimes. Earth, planets and space, 52(10), 877-880, 2000. https://earth-planets-space.springeropen.com/ar ticles/10.1186/BF03352299
2. J. Wang and J. Wang, Comparing long baseline results from GPS and GPS/GLONASS. In CombinedInt. Symp. & Exhibition on Geoinformation & GNSS, Johor Bahru, Malaysia,5-7, 2007. https://www. researchgate.net/ profile/Jinling-Wang-8/publication/252717012_Comp aring_Long_Baseline_Results_from_GPS_and_GPSGLONASS/links/0deec52c2163d3e413000000/Comparing-Long-Baseline-Results-from-GPS-and-GPS-GLONASS.pdf
3. C. Bruyninx. Comparing GPS-only with GPS + GLONASS positioning in a regional permanent GNSS network. GPS Solu-tions, 11, 97–106, 2007. https:// link.springer.com/article/10.1007/s10291-006-0041-9
4. C. Cai and Y. Gao, Precise Point Positioning Using Com-bined GPS and GLONASS Observations. Journal of Global Positioning Systems, 6(1), 13-22, 2007. https ://www.scirp.org/html/348.html?pagespeed=noscript
5. M. Azab, A. El-Rabbany, M. N. Shoukry & R. Khalil. Precise Point Positioning Using Combined GPS/GLONASS Measurements. FIG Working Week Bridging the Gap between Cultures Marrakech, Morocco, 18-22 May, 2011. http://www.fig.net/resourc es/proceedings/fig_proceedings/fig2011/ppt/ts04j/ts04j_azab_elrabbany_et_al_5277_ppt.pdf
6. S. Alcay, C. Inal, and C. Ozer, Contribution of GLONASS Observations on Precise Point Positioning. FIG Working Week 2012, knowing to manage the territory, protect the environ-ment, evaluate the cultural heritage. Rome, Italy, 6-10 May, 2012.
7. A. B. Anquela, A. Martín, J. L. Berné and J. Padín, GPS and GLONASS Static and Kinematic PPP Results. Journal of Surveying Engineering, 47, February,2013. https://ascelibrary.org/doi/abs/10.1061/(ASCE)SU.1943-5428.0000091
8. J. Mohammed, T. Moore, C. Hill, R. M. Bingley and D. N. Hansen, An assessment of static precise point positioning using GPS only, GLONASS only, and GPS plus GLONASS, Measurement 88, 121–130, 2016. https://www.sciencedirect.com/science/article/pii/S0263224116300161

9. M. Abd-Elazeem, A. Farah, and F. A. Farrag, Cut-Off elevation angle effect on GPS positioning accuracy. Al-Azhar University Engineering Journal, JAUES, 5(1), 565 -570, 2010.
10. T. Ning and G. Elgered, Trends in the atmospheric water vapor content from ground-based GPS: The impact of the elevation cutoff angle. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 5(3), 744-751, 2012. https://ieeexplor e.ieee.org/abstract/document/6185695
11. A. Martín, A. B. Anquela, J. L. Berné and M. Sanmartín, Kinematic GNSS-PPP results from various software packages and raw data configurations, Sci. Res. Essays, 7(3), 419-431,2012. https://riunet.upv.es/handle /10251 /34504
12. A. Martín, A. B. Anquela, R. Capilla and J. L. Berné, PPP technique analysis based on time convergence, repeatability, IGS products, different software processing, and GPS 1 GLONASS constellation. J. Surv. Eng., 137(3), 99-108, 2011. https://ascelibrary. org/doi/abs/10.1061/(ASCE)SU.1943-5428.0000047
13. GMV,https://www.gmv.com/en-es/products/space/mag icpppr ,Accessed 28 June 2020
14. R. Píriz, A. Mozo, P. Navarro and D. Rodríguez, MagicGNSS: Precise GNSS products out of the box. In Proceedings of the 21st International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS 2008), 1242-1251, 2008. https://www.ion.org/publications/abstract.cfm?articleID=8036
15. S. Kalaycı, SPSS uygulamalı çok değişkenli istatistik teknikleri, Asil Yayın Dağıtım Ltd.,Şti. 5. Baskı, Kızılay, Ankara, ISBN: 975-9091-14-3, 2010.