Verification of the Usefulness of the Trimble Rtx Extended Satellite Technology with the Xfill Function in the Local Network Implementing Rtk Measurements

Abstract

The paper presents the method of satellite measurements, which gives users the ability of GNSS continuous precise positioning in real time, even in the case of short interruptions in receiving the correction of the local ground system of measurements support. The proposed method is a combination of two satellite positioning technologies RTN GNSS and RTX Extended. In technology RTX Extended the xFill function was used for precise positioning in real time and in the local reference system. This function provides the ability to perform measurement without the need for constant communication with the ground support satellite system. Test measurements were performed on a test basis located in Krakow, and RTN GNSS positioning was done based on the national network of reference stations of the ASGEUPOS. The solution allows for short (up to 5 minutes) interruptions in radio or internet communication. When the primary stream of RTN correction is not available, then the global corrections Trimble xFill broadcasted by satellite are used. The new technology uses in the real-time data from the global network of tracking stations and contributes significantly to improving the quality and efficiency of surveying works. At present according to the authors, technology Trimble CenterPoint RTX can guarantee repeatability of measurements not worse than 3.8 cm (Trimble Survey Division, 2012). In the paper the comparative analysis of measurement results between the two technologies was performed: RTN carried out in the classic way, which was based on the corrections of the terrestrial local network of the Polish system of active geodetic network (ASG-EUPOS) and RTK xFill technology. The results were related to the data of test network, established as error free. The research gave satisfactory results and confirmed the great potential of the use of the new technology in the geodetic work realization. By combining these two technologies of GNSS surveying the user can greatly improve the overall performance of real-time positioning.

Accuracy Evaluation of Real-Time GNSS Precision Positioning with RTX Trimble Technology

“…They require the use of either a temporary or permanent base station. Performance is mostly dependent on the ionospheric delay witch depends on the distance from the base station [6]. Nowadays, most of the area has cellular coverage.…”

“…The technology allows obtaining high accuracy position without using differential measurements. It is possible through precise satellite orbit, exact information about satellites clocks and atmosphere delays [8]. In case of PPP, the convergence time might be a huge barrier.…”

“…In case of PPP, the convergence time might be a huge barrier. The GNSS measurement session time depends on atmospheric influence and geometry of constellation [6]. There is PPP both in static and kinematic mode [9,10].…”

“…Researches indicated that northeast precision of static solution can reach millimeter level, whereas in case of ellipsoid elevation is 1-2 cm for daily period of observation [11]. The RTX technology proposed by Trimble Company has been developing at a fairly rapid pace for several years and can permanently increase the possibilities of GNSS measurements [8]. It offers cm-level GNSS positioning through the CENTERPOINT RTX TM service.…”

CenterPoint RTX Teknolojisinin Doğruluk ve Tekrarlana bilirliğinin Araştırılması

“…Bu teknik kullanıcılara tek bir GNSS alıcısıyla çözüm sağlaması sebebiyle klasik RTK tekniğine kıyasla daha ekonomik çözüm sunmaktadır. Ancak, mevcut sistemin altyapı kurulum maliyetinin çok yüksek olması (Eissfeller, 2012), bazı sistemlerde kullanıcıların servis hizmeti alabilmesi için belirli bir ücret ödemek zorunda olması, tekniğin GSM hattına bağımlılığı (Alkan, Ozulu, & İlçi, 2017) ve kullanımın ağ ile sınırlı olması dolayısıyla küresel ölçekte çözüm sunamaması (Hutton et al, 2016) (Chen et al, 2011;Krzyżek, 2013;Leandro et al, 2012;Nardo et al, 2015) (Doucet et al, 2012;Siejka, 2014). Bu merkezlerde hassas uydu konum, saat ve hız kestirimleri, atmosferik veriler, taşıyıcı haz tamsayı belirsizlikleri ve yer dönme parametreleri vb.…”