Çoklu-GNSS çözümlerinin performansının internet tabanlı Trimble RTX servisi ile incelenmesi

Abstract

Günümüzde jeodezik amaçlı yapılan çalışmaların birçoğunda Küresel Konumlama ve Uydu Sistemleri’ne (Global Navigation Satellite System, GNSS) ait veriler kullanılmaktadır. GNSS yapısında, GPS, GLONASS, Galileo ve BeiDou uydu sistemleri beraber değerlendirilerek konum bilgisi elde edilebilmektedir. Uluslararası GNSS Servisi (International GNSS Service, IGS) bu amaç doğrultusunda farklı sinyal ve uydu sistem verilerinin toplanması, izlenmesi ve analiz edilmesi için Multi-GNSS Experiment (MGEX) adında bir proje başlatmıştır. Çoklu-GNSS çözümlerinin kullanılmaya başlamasından dolayı, bu çözümlerden elde edilen konum doğruluğunun belirlenmesi kullanıcılar açısından büyük önem arz etmektedir. Bu nedenle bu çalışmada; 10 noktaya ait GNSS verileri; GPS, GPS/GLONASS, GPS/GLONASS/Galileo ve GPS/GLONASS/Galileo/BeiDou olmak üzere 4 farklı senaryo ile değerlendirilmiş ve doğruluk analizleri gerçekleştirilmiştir. GNSS verilerinin değerlendirilmesi bir internet tabanlı yazılım olan ve Çoklu-GNSS hassas mutlak nokta konumlama (Precise Point Positioning, PPP) çözüm kapasitesine sahip Trimble RTX servisi ile gerçekleştirilmiştir. Sonuçlar, sadece GPS çözümleri yerine farklı uydu kombinasyonlarını birlikte kullanarak daha yüksek doğrulukla konum bilgisi elde edilebileceğini göstermiştir. Ayrıca, Çoklu-GNSS çözüm doğruluklarının gözlem süresi ve enlem bilgisine bağlı olup olmadığı da incelenmiştir. Sonuçlara göre Çoklu-GNSS çözüm doğruluklarının sadece gözlem süresine bağlı olarak değiştiği vurgulanmıştır.

Keywords

• Çoklu-GNSS
• Doğruluk
• Hassas mutlak nokta konum belirleme
• Trimble RTX servisi

Investigation of the performance of the Multi-GNSS analysis with web based Trimble RTX service

Abstract

Nowadays, Global Navigation Satellite Systems (GNSS) data are used in most of the geodetic studies. Positioning information can be obtained by using GPS, GLONASS, Galileo and BeiDou in the structure of the GNSS. International GNSS Service (IGS) has initiated a project, called Multi-GNSS Experiment (MGEX), to collect, track and analyze different signals and satellite system data. Since, the Multi-GNSS solutions have started to use, positioning accuracy obtained from Multi-GNSS solutions is very important for users. Therefore, in this study, GNSS data of 10 stations were analyzed in 4 different scenarios as GPS, GPS/GLONASS, GPS/GLONASS/Galileo and GPS/GLONASS/Galileo/BeiDou. The GNSS data were processed using Trimble RTX service which is a web based precise point positioning (PPP) software that is capable of processing Multi-GNSS data. Results have demonstrated that, it has been shown that the higher positioning accuracy can be obtained using different satellite systems together, instead of using GPS-Only. Moreover, accuracy of Multi-GNSS solutions was investigated whether it depends on session duration and latitude or not. According to the results, it was emphasized that accuracy of Multi-GNSS solutions only depends on session duration.

Keywords

• Multi-GNSS
• Accuracy
• Precise point positioning
• Trimble RTX service

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