The European Commission (EC) originally proposed ideas for a European Galileo satellite navigation system in 1999. A four-phase development is planned, involving investment from both the public and ...commercial sectors. Galileo is intended for both public and government use; the system is administered and operated by civil administration. Galileo will consist of a constellation of 30 satellites, a number of globally situated ground stations, and a ground control and monitoring system – all of which are quite similar to the structure, format, and layout of GPS. This document discusses an experiment at the project site that used the static approach to integrate GPS, GLONASS, GALILEO, Beidou, and QZSS signals. This research analyses the possible precision of GPS-only and GPS/GLONASS/GALILEO/Beidou/QZSS. These results suggest that combining a GPS system with GALILEO, GLONASS Beidou, and QZSS is preferable for surveying purposes. Integrating GPS/GLONASS/GALILEO/Beidou/QZSS static measurements in the study region with 0–120 millimetre accuracy looks to be possible in three days.
Modern karayolu ve demiryolu ulaştırma yapılarında geçiş eğrileri, doğru ve daire kadar önemli olan güzergâh öğeleridir. Merkezkaç kuvvetinin aniden değişmesini önlemek için, hareketin keskin bir ...eğri üzerindeki etkisinden dolayı geçiş eğrisi uygulanması gerekmektedir. Yıllar içinde, geçiş eğrisi olarak klotoid uygulanması dünyanın birçok ülkesinde yaygınlaşmıştır. Ancak klotoid uygulamasının yüksek hızlarda yolun güvenliğinde ve konforunda sorunlara sebep olması nedeniyle farklı geçiş eğrilerine ihtiyaç duyulmuştur. Bu kapsamda; yüksek hızdaki araçlar için klotoidin oluşturduğu yol dinamikleri ile ilgili sorunları gidermek amacıyla sinüsoid ve dördüncü dereceden parabol geçiş eğrileri kullanılmıştır. Klotoidin basit matematiksel çözümlemesine karşılık, sinüsoid ve dördüncü dereceden parabol geçiş eğrilerinin koordinatlarının hesaplanması, karmaşık matematiksel çözümler içermektedir. Bu çalışmada klotoid, sinüsoid ve dördüncü dereceden parabolün temel matematiksel özellikleri sunularak, herhangi bir bilgisayar yazılımı kullanmaksızın, Simpson kuralı kullanılarak ile sinüsoid ve dördüncü dereceden parabol geçiş eğrilerinin koordinatlarının sayısal integrasyon ile sinüsoid ve dördüncü dereceden parabol geçiş eğrilerinin koordinatlarının proje amacına uygun hassasiyet ile hesaplandığı gösterilmiştir.
The North Anatolian Fault Zone (NAFZ), which produced the 1999 Golcuk-Izmit earthquake, extends in three branches in the Marmara Region and causes a significant earthquake hazard. This study consists ...of processing and analysing data from three stations (TUBI, MER1 and DUMT) that are part of the IGS and MAGNET (Marmara Permanent GPS Network) network and are situated close to the epicentre of the Golcuk-Izmit earthquake. By analysing the time series generated from three daily solutions (TUBI, DUMT and MER1 stations), the displacements due to the earthquake were computed (17 August 1999). When GPS processing on 15–16 August 1999, especially for the Golcuk-Izmit earthquake, is examined, it is possible to interpret this situation as a precursor of the earthquake, as a result of the examination of the data obtained from the process of 15 and 16 August 1999. On August 17, 1999, the movement at the TUBI, DUMT and MER1 points before the earthquake was 2–6 cm while it was computed on average 38–86 cm during and after the earthquake. The earthquake clearly had substantial impact on the horizontal components on 17 Aug 1999. The horizontal coordinates of TUBI, DUMT and MER1 stations have changed by around 49–87 cm, and the height components have changes by around 14–137.10 cm based on the time series of coordinate discrepancies.
Post-processing kinematics (PPK) is positioning process in which signals received from a mobile receiving device store location data can be adjusted using corrections from a reference station after ...data has been collected. The processed kinematic screening method provides the surveyor with a technique for high production survey measurements and can be used in areas with minimal satellite barriers. PPK uses significantly reduced observation times compared to static or fast static observations. This method requires least squares adjustment or another multiple basic statistical analysis that can produce a weighted average of observations. The results obtained using PPK are between 1 cm and 3 cm for horizontal coordinates and from 1 cm to 10 cm for vertical coordinates.
People are fascinated today more than ever by the polar regions of the Earth. One reason for this is that wide expanses of the Arctic and Antarctic have not been explored and are therefore still ...viewed as frontier regions. Another is that they both have very diverse histories with regard to their origins and ice formation. Their numerous aspects still pose many puzzles for science today. The regions of the Earth designated as polar are those areas located between the North or South Pole and the Arctic or Antarctic Circles, respectively. The northern polar region, called the Arctic, encompasses the Arctic Ocean and a portion of some surrounding land masses. The southern polar region, called the Antarctic, contains the continent of Antarctica and areas of the surrounding Southern Ocean. In this paper three tests (2000, 2010 and 2021) of continuous GNSS data recorded by 8 permanent International GPS Service (IGS) stations in both Polar Regions have been processed by using CSRS-PPP Software for geodetic networks. The results also show that all GNSS provide good visibility with low elevation angles, whereas with high elevation angles, which might be needed due to natural barriers, the GLONASS and other satellites provides the highest number of visible satellites. Consequently, the mean motion of the study area was found approximately 7–15 cm for horizontal components (X–Y) and 6 cm for vertical components (Ellipsoidal Height) on the eight IGS points in the both poles.
This article evaluates the accuracy and performance of GPS positioning near a forest area. In such cases, positions are calculated from weak signals that tend to be less accurate. Moreover, the ...results show that there were significant differences depending on season (May vs. October) regarding the accuracy and precision of the measured coordinates; also, accuracies were different depending on the seasonal forest characteristics. Therefore, practical recommendations for each case were established in order to help foresters select the most suitable situation. The results indicated that the season was a significant factor for the GPS surveys.
Despite advances in GPS equipment installed at permanent sites, multipath still remains a significant error source. Strobe Correlator technology greatly reduces GPS multipath signals, which can occur ...when the GPS signals are reflected off tall buildings or other obstructions before captured by the receiver and, thus, increase the distance a signal travels and reduce the accuracy. A GPS receiver using Strobe Correlator performs a series of complex calculations to restore positioning accuracy. I present a technique for evaluating and correcting the multipath at GPS antenna by utilizing the Enhanced Strobe Correlator (ESC) especially in RTK GPS applications. The advanced technique of Enhanced Strobe Correlation is discussed here. In addition, the performance of the technique is presented with the experiments from real multipath environments comparing RTK GPS results with terrestrial ones.
Integrated Inertial Measurement Unit (IMU) and electronic compass; small, sturdy form factor; supports all communications, satellites, and constellations (Revolutionary 9 axis IMU and ultra-compact ...3-axis e-Compass). By integrating a 9-axis IMU with a digital compass, the Topcon Hiper Versatile Global Navigation Satellite System (VR GNSS) receiver can correct for up to 15 degrees of pole tilt. It may be now measured all the way to the edge/corner of a building without requiring an offset. The emerging technology makes up for the fact that plum field surveys can be off by up to 15 degrees. The accuracy of measured building corners is investigated in this study using Topcon Inertial Levelling Technology (TILT) in the IMU and e-Compass. The results of a case study of 5, 10, 15 degree tilt angles show that a 3D positioning accuracy of about 10 cm is achievable even when the pole is tilted.
Galileo Uydu Sistemi ve Sinyal Yapısı PIRTI, Atınç; HOŞBAŞ, Ramazan Gürsel; ŞENEL, Burak ...
Geomatik (Online),
12/2021, Letnik:
6, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Küresel konum belirleme sistemleri günümüzde devrim olarak nitelendirilebilir. Bu sistemler herhangi bir cismin yaklaşık olarak konumunun belirlenmesinde, ulaşım araçlarının navigasyonunda, birçok ...ölçme işleminde ve buna benzer hayatı kolaylaştıracak birçok alanda kullanılabilmektedir. Çok hassas zaman bilgileri aracılığıyla üç boyutlu uzay geriden kestirme yöntemi sonucunda yüksek doğruluk ve hızlı işlem süreleriyle en çok tercih edilen sistemler olmuşlardır. Dünya çapında Global Konum Belirleme Sistemi (Global Positioning System-GPS), GLONASS (Globalnaya Navigatsionnaya Sputnikova Sistema) sistemleri aktif olarak kullanılmaktadır. Bu iki sistemin yanında GALILEO uydu sistemi de emin adımlarla ilerlemektedir. GALILEO sistemi sivil olarak birçok alana hizmet vermeyi planlamaktadır. Bu çalışmada GALILEO’nun özelliklerine, sinyallerine, ortaya çıkış aşamalarına, diğer sistemlerle arasındaki farklılıklara ve neden ihtiyaç duyulduğuna değinilmektedir.
The purpose of this study is to evaluate the repeatability of RTK GPS method under varying satellite configurations by using different reference points. Furthermore, we conducted one way Analysis of ...Variance (ANOVA), which is a powerful tool for comparing the variability of related types of measurements. Multi-reference station is a well-known approach in RTK GPS. Using multi-reference points is an effective way to achieve consistent accuracy in the whole net by making errors less distance dependent on the reference stations. It is possible to achieve high reliability and availability by using multi-reference stations. If one station goes down or starts to provide suspicious values, it is possible to compensate the situation with other stations, while this is not possible when a single reference station fails. Here we present ANOVA which is an effective method to check the quality of corrections generated from each reference station.
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