The growing availability of low-cost dual-frequency GNSS receivers is enhancing their suitability for various kinds of geodetic applications. Geodetic monitoring of the continuous crustal deformation using GNSS time series analysis is one of the commonly used geodetic applications. To maintain the most accurate estimated parameters such as secular velocity, seasonal signal parameters and offsets, geodetic-grade GNSS receivers are commonly used in the GNSS time series analysis. However, due to the increasing availability of low-cost dual-frequency GNSS receivers and advancements in software and hardware, these receivers have now reached a level that supports the GNSS time series analysis. In this study, over a year of multi-GNSS PPP-AR time series of the u-blox ZED-F9P low-cost GNSS receiver are investigated by evaluating the accuracy of the estimated parameters, comparing them with data from a geodetic-grade GNSS receiver monumented on a building roof. The results show that the minimum detrended standard deviation obtained from White Noise (WN) estimation is achieved using GPS + GLONASS + Galileo PPP for both receivers. The computed annual velocity and amplitude differences obtained from the GNSS time series between the u-blox ZED-F9P and the geodetic-grade GNSS receivers using GPS + GLONASS + Galileo PPP-AR are found as 0.6 mm / 0.4 mm / 0.8 mm and 1.5 mm / 0.4 mm / 0.2 mm for north, east, and up components, respectively. (c) 2025 COSPAR. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Cycle slips are events in which a receiver experiences a disruption in its carrier phase lock to a Global Navigation Satellite System (GNSS) signal. Accurate detection of cycle slips is essential to prevent degradation of positioning accuracy when carrier-phase observations are used. In this study, the reliability of the Loss of Lock Indicator (LLI) index in RINEX observation files from six different receiver types was investigated and compared with the Phase Geometry-Free and Hatch-Melbourne-Wu & uml;bbena (GF + HMW) cycle slip detection algorithm. Precise Point Positioning (PPP) in stand-alone mode was performed using GPS, GLONASS, Galileo, and BDS-3 observations, applying either the LLI index alone or the GF + HMW cycle slip detection algorithm. The resulting RMSEs and overlaps between the methods were analyzed based on receiver types. The results show that the most reliable LLI data comes from LEICA and TRIMBLE receivers, while SEPTPOLARX5-TR, SEPTPOLARX5, and JAVAD receivers exhibited relatively poor LLI performance. PPP results showed that the LLI, which outperforms GF + HMW on the ionospherically quiet days for some receivers and GNSS constellations, performs worse on ionospheric scintillation days. (c) 2026 COSPAR. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Thanks to the increasing number of low-cost dual-frequency GNSS receivers available on the market, the usability of these receivers for geodetic applications is increasing. Recently, PRIDE Lab at GNSS Research Center of Wuhan University has started to produce GNSS observable-specific phase biases for all-frequency. This enables precise point positioning with ambiguity resolution (PPP-AR) not only for conventional frequencies but also for other arbitrary frequencies. In this work, static and kinematic PPP-AR precision of the u-blox ZED-F9P low-cost GNSS receiver are investigated by comparing it with a geodetic-grade GNSS receiver using GPSonly, Galileo-only, and GPS + Galileo combinations for nearly two months period. Wide-lane (WL) and Narrow-lane (NL) AR fixing rates, cycle slips, code multipath, and frequency availability are also investigated for both receivers. In the positioning domain, GPSonly, Galileo-only, and GPS + Galileo PPP positioning precision using float ambiguities is significantly improved after AR for both receivers. GPS + Galileo PPP provides the best precision comparing with the other PPP solutions for both receivers using float and fix ambiguities. For static GPS + Galileo PPP-AR, the standard deviation of north, east, and up components are computed as 2.7/1.7/3.2 mm and 2.2/2.3/5.4 mm for the geodetic receiver and the u-blox receiver, respectively. The results also reveal that kinematic PPP-AR for the u-blox receiver is not as reliable as the geodetic-grade receiver yet suggesting potential for improvement in future iterations. (c) 2024 COSPAR. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

This study examines the Vertical Total Electron Content (VTEC) estimation performance of multi-instruments on a global scale during different ionospheric conditions. For this purpose, GNSS-based VTEC data from Global Ionosphere Maps (GIMs), COSMIC (F7/C2)—Feng–Yun 3C (FY3C) radio occultation (RO) VTEC, SWARM–VTEC, and JASON–VTEC were utilized. VTEC assessments were conducted on three distinct days: geomagnetic active (17 March 2015), solar active (22 December 2021), and quiet (11 December 2021). The VTEC values of COSMIC/FY3C RO, SWARM, and JASON were compared with data retrieved from GIMs. According to the results, COSMIC RO–VTEC is more consistent with GIM–VTEC on a quiet day (the mean of the differences is 4.38 TECU), while the mean of FY3C RO–GIM differences is 7.33 TECU on a geomagnetic active day. The range of VTEC differences between JASON and GIM is relatively smaller on a quiet day, and the mean of differences on active/quiet days is less than 6 TECU. Besides the daily comparison, long-term results (1 January–31 December 2015) were also analyzed by considering active and quiet periods. Results show that Root Mean Square Error (RMSE) values of COSMIC RO, FY3C RO, SWARM, and JASON are 5.02 TECU, 6.81 TECU, 16.25 TECU, and 5.53 TECU for the quiet period, and 5.21 TECU, 7.07 TECU, 17.48 TECU, and 5.90 TECU for the active period, respectively. The accuracy of each data source was affected by solar/geomagnetic activities. The deviation of SWARM–VTEC is relatively greater. The main reason for the significant differences in SWARM–GIM results is the atmospheric measurement range of SWARM satellites (460 km–20,200 km (SWARM A, C) and 520 km–20,200 km (SWARM B), which do not contain a significant part of the ionosphere in terms of VTEC estimation.

The ionosphere shows regular changes such as daily, 27 days, seasonal, semi-annual, annual, and 11 years. These changes can be modeled and their effects largely determined. However, in addition to regular changes, irregular changes occur in the ionosphere due to space weather conditions, natural disasters, and human-induced irregularities. GNSS is one of the instruments along with many others that can give a piece of information on the ionospheric state. Various indices/parameters are used to determine the effect of space weather conditions. The well-known ones are solar activity indices, geomagnetic storm indices, magnetic field components, proton density, and proton flux parameters. It is important to take all of these indices into consideration when investigating the source of the anomaly. Considering only some of them may lead to incorrect inferences about the source of possible anomalies. To carry out comprehensive research in this field, it is necessary to analyze a very large data set. This indicates the requirement for an automatic system. With the Global and Regional Ionosphere Monitoring System (GRIMS) designed within the scope of this study, the ionosphere can be monitored globally and regionally. The GRIMS is online at https://www.online-grims.com/ . By using Global ionospheric maps and GNSS receiver data, global, regional, and station-specific anomalies can be detected regularly through methods such as HDI (Highest Density Interval) and ARIMA (Autoregressive Integrated Moving Average). GRIMS gathers space weather-related parameters from ionospheric data centers to help users interpret the situation, and it allows users to download the results and request data for specific days. The details of the experimental results and output products of the system designed during the geomagnetic active days of March 17, 18, 2015 are given in this paper. Moreover, geomagnetic active days that occurred between 2000 and 2023 are given in the GRIMS.

Recently, low-cost GNSS receivers have played a significant role in displacement monitoring studies due to the increasing availability of mass-market applications. In this work, the performance of static and kinematic PPP-AR using a low-cost u-blox ZED-F9P GNSS receiver in monitoring displacements is investigated by comparing it with a geodetic-grade GNSS receiver using a displacement simula-tion apparatus. The capability to determine the horizontal displacement direction is also investigated for both receivers. The results showed that one-sigma horizontal / vertical RMSEs computed from the true displacements and computed displacements are 1.4 / 5.6 mm and 2.6 / 8.4 mm for the geodetic and u-blox receivers, respectively, using 24-h data with static GPS + GLONASS PPP-AR. It is found that GLONASS contribution to GPS-only static PPP is more evident for the u-blox receiver compared with the geodetic one. RMSEs are found to be higher as observation times are decreased. The post-processed kinematic test results showed that minimum 10 / 20 and 20 / 30 mm horizontal / vertical dynamic displacements can be visually detected as an offset from the daily time series for the geodetic and u-blox receivers, respectively.(c) 2023 COSPAR. Published by Elsevier B.V. All rights reserved.

As of 2021, a total of four different GNSS constellations - namely, GPS, GLONASS, Galileo, and BDS-3 - can be used with Full Operational Capability (FOC). In this work, the contribution of BDS-3 FOC to GPS + GLONASS + Galileo (GRE) PPP-AR is inves-tigated, considering the three different cut-off angles (7 degrees, 30 degrees, and 45 degrees) and different lengths of static observation sessions (24-, 12-, 6-, 3-, 1-, 0.5-, 0.25-hour). The data of 31 IGS-MGEX stations is processed with GRE PPP-AR and GREC3 (GPS + GLONASS (using float mode) + Galileo + BDS-3) PPP-AR modes. The results showed that BDS-3 degraded the horizontal (except for 24-h sessions) and ver-tical accuracy of static GRE PPP-AR solutions regardless of the elevation cutoff angle and observation time. The kinematic results showed that BDS-3 significantly contributed to the accuracy of GRE kinematic PPP-AR for 30 degrees and 45 degrees cutoff angles. The convergence time analysis showed that BDS-3 only contributes to GRE kinematic PPP-AR for the vertical component.(c) 2022 COSPAR. Published by Elsevier B.V. All rights reserved.

The positioning performance of widely used real-time precise point positioning (RT-PPP) software packages BNC, RTKLIB, and PPP-WIZARD were tested in terms of convergence time and accuracy. The convergence time of PPP-WIZARD solutions is reduced by ambiguity resolution (AR). The GPS + GLONASS + GALILEO (GRE) mode improved the convergence time of GPS + GALILEO (GE) mode by 22.0%, 15.5%, 17.1%, and 11.4% for the BNC, RTKLIB, PPP-WIZARD (AR) and PPP-WIZARD, respectively. For the GRE mode, RMSEs of the BNC, RTKLIB, PPP-WIZARD (AR), and PPP-WIZARD software packages in the horizontal/vertical component are 3.8/5.6, 2.6/6.2, 3.3/6.5, 4.3/7.0 cm, respectively. In comparison with the IGS-ZTD (International GNSS Service ZTD), BNC, RTKLIB, PPP-WIZARD (AR), and PPP-WIZARD solutions show a mean bias of 0.28, -0.72, 2.80, and 2.83 cm, respectively in GE mode. The GRE mode reduced the RMSEs of the ZTD estimations of BNC, RTKLIB, PPP-WIZARD (AR) and PPP-WIZARD by 2.9%, 5.1%, 0.6%, and 0.4% respectively.

In the middle of 2011, Trimble introduced the RTX correction service to support RT-PPP applications. In this study, the performance of Trimble RTX correction service is investigated over a one-month period using five different GNSS constellations – namely, GPS-only, GPS + GLONASS, GPS + Galileo, GPS + GLONASS + Galileo, and GPS + GLONASS + Galileo + BeiDou. The results show that positioning accuracy and convergence time are significantly improved with the use of the multi-GNSS constellation compared with the GPS-only solution. The result of the converged positioning accuracy indicates that the GPS + GLONASS + Galileo + BeiDou combination improves the accuracy by 63%, 54%, and 60% for north, east, and up components, respectively, compared with the GPS-only solution. The mean convergence time is reduced by the GPS + GLONASS+ Galileo + BeiDou combination by 70%, 71%, and 38.6% compared with the GPS-only solution in the north, east, and up components, respectively. 1.2 (north), 1.5 (east), and 2.3 cm (up) root mean square errors (RMSEs) of converged positioning from the GPS + GLONASS + Galileo + BeiDou combination are computed.

Günümüzde tam kapasite ile konum belirleme hizmeti sunan dört Küresel Konum Belirleme Sistemi (GNSS) bulunmaktadır. Bunlar GPS, GLONASS, Galileo ve BeiDou’ dur. GPS ve GLONASS uzun yıllardır hizmet verirken, Galileo ve BeiDou son yıllarda dahil olmuştur. Bu çalışmada bu dört GNSS sisteminin 1. ve 2. temel frekanslarının doluluk durumu incelenmiştir. Bu amaçla 05.06.2023 tarihine ait 322 IGS-MGEX istasyonlarına ait (bu tarih için igs.ign.fr adresindeki bütün IGS istasyonları) veriler dikkate alınmıştır. Elde edilen sonuçlara göre GPS frekans doluluk oranlarının diğer uydu sistemlerine göre bir miktar daha iyi olduğu, doluluk oranlarının %96’nın üzerinde olduğu görülmüştür. Diğer uydu sistemlerinde de doluluk oranları GLONASS ikinci frekans hariç %94’ün üzerinde olduğu belirlenmiştir.

Thanks to the development of the real-time kinematic (RTK) algorithm and the emerging Global Navigation Satellite System (GNSS), especially for Galileo and BeiDou-3, reliable positioning accuracy for medium and long-baseline RTK became possible globally. Moreover, with the development of the GNSS receiver hardware, baseline length limitations due to radio-based communications are removed thanks to internet-based communication. In this work, single-baseline RTK, incorporated partial ambiguity resolution with troposphere and ionosphere weighting, using GPS (G), Galileo (E), BeiDou-3 (C3) and multi-GNSS (GE and GEC3), is conducted with real GNSS data of EUREF Permanent GNSS network under three different cutoff angles (10 degrees, 20 degrees, and 30 degrees) for six different lengths of baselines (similar to 50, similar to 150, similar to 250, similar to 350, similar to 450, and similar to 550 km). The results show that the multi-GNSS RTK solution significantly contributed to the positioning accuracy and convergence time of the single-system RTK solutions. Based on the results, non-available epoch-wise solutions for the high-degree cutoff angles are more obvious for the single-system RTK, whereas multi-GNSS solutions provide 100% solutions for each cutoff angle and baseline. The results indicate that instantaneous and a few epochs single-epoch ambiguity resolution is feasible for 50, 150, 250 and 350 km baseline lengths for multi-GNSS RTK. Based on the positioning results, horizontal-vertical positioning improvements of multi-GNSS RTK (GEC3) compared with the single-system GPS RTK are found as 50%-37%, 40%-35%, 55%-47%, 53%-54%, 57%-49% and 57%-49% for 50, 150, 250, 350, 450 and 550 km, respectively, under a 10 degrees cutoff angle. For 20 degrees and 30 degrees cutoff angles, the accuracy improvements are much higher. The convergence time improvements (n/e/u) of multi-GNSS RTK (GEC3) compared with the single-system GPS RTK are found as 86/92/75%, 77/67/72%, 75/77/83%, 53/56/52%, 69/49/62%, and 52/45/39% for 50, 150, 250, 350, 450 and 550 km, respectively, under a 10 degrees cutoff angle

Thanks to the rapidly emerging low-cost dual-frequency GNSS receivers, a feasible alternative for geodetic-grade GNSS receivers became available for some GNSS applications. In this study, the performance of data integrity and quality of a low-cost ZED-F9P u-blox GNSS receiver was investigated by comparing it with a geodetic-grade GNSS receiver. Availability of the epoch and phase/code signal channels, signal-to-noise ratio (SNR), code multipath, and cycle slips were analyzed for the geodetic-grade and low-cost ZED-F9P u-blox GNSS receivers. One month’s data of GPS, GLONASS, and Galileo constellations were analysed using the RINEX files of the receivers. The results showed that the epoch availability of the geodetic-grade and u-blox GNSS receiver is comparable to each other, while the availability of phase/code signal channels of the geodetic-grade receiver is higher than the u-blox receiver. In terms of data quality, SNR values from both receivers are comparable, while the multipath level of the u-blox GNSS receiver is significantly higher than the geodetic-grade one. The results also showed that the number of cycle slips of the u-blox receiver is significantly higher than the geodetic-one.

The Real Time Kinematic (RTK) method is widely used in the land surveying. Whereas RTK method has the advantage of practical use, positioning accuracy depends mostly on the baseline length due to the atmospheric errors. In general, RTK measurements are made by using GPS and GLONASS satellite systems. For this reason, the positioning performance of the technique is adversely affected under restricted satellite geometry conditions such as urban canyons. At present, most receivers on the market have the ability to track signals of Galileo and BeiDou satellites. Therefore, in this study, the positioning performance of RTK with different satellite combinations (GPS-only, GPS+GLONASS, GPS+GLONASS+GALILEO+BeiDou) was examined with a comparative approach. A field test was carried out considering approximately 20, 40, 60, and 80 km length of baselines. Three different cut off elevation angles – namely, 10°, 20°, and 30° – were chosen for the field test. The results were investigated in terms of accuracy and precision. Also, the ground truth coordinates of the rovers were obtained by post-processing relative method using GAMIT/GLOBK software. The results showed that multi-GNSS combinations provided better repeatability at the 10° cut off angle option. The accuracy of GPS-only solutions varied between 0.63/2.17 cm and 2.40/4.94 cm for horizontal and vertical components, respectively. However, the multi-GNSS combinations did not have a remarkable superiority in terms of position accuracy even at high satellite cut off angle (30°) compared to the GPS-only RTK.

Küresel Navigasyon Uydu Sistemleri (GNSS) jeodezik ölçmeler, araç takip sistemleri, turizm, tarım, askeri, deformasyon ölçmeleri ve arama kurtarma çalışmaları gibi birçok farklı alana hizmet vermektedir. GNSS teknolojileri ayrıca güneş aktiviteleri, iyonosfer ve troposferin incelenmesine de olanak sağlamaktadır. Bu çalışmada, Hassas Nokta Konum Belirleme (PPP) yöntemi ile elde edilen troposferik gecikmelerden yararlanarak Yoğuşabilir Su Buharı (PWV:Precipitable Water Vapor) miktarının belirlenmesi ve elde edilen bu değerlerin günümüzde referans olarak kabul gören radyosondadan elde edilen PWV değerleri ile karşılaştırılması yapılmıştır. Çalışma kapsamında Türkiye’de bulunan Samsun, Erzurum, İstanbul ve İzmir radyosonda istasyonları ve yakın konumlarında bulunan SAM1, ERZR, ISTN ve IZMI CORS-TR istasyonlarının 2016-2020 yıllarına ait verileri kullanılmıştır. GNSS verilerinin değerlendirilmesinde CSRS-PPP servisinden yararlanılmıştır. Elde edilen sonuçlar incelendiğinde iki yöntemle elde edilen PWV değerlerinin uyum içerisinde olduğu ve çoğunlukla benzer trend gösterdiği görülmüştür.

One of the major error sources for Global Navigation Satellite Systems (GNSS) is the ionosphere layer. In addition to regular changes in the ionosphere, irregular changes due to space weather conditions also occur. One of the space weather phenomena is geomagnetic storm. In this study, the influence of changes in the ionosphere in case of geomagnetic storm on kinematic Precise Point Positioning (PPP) was investigated. For this purpose, 12 intense geomagnetic storms were selected between 2000 and 2018. Using the global ionosphere maps, the anomaly regions were determined and UCLP—LPGS stations were selected from the northern and southern hemispheres, respectively. The Total Electron Content (TEC) and kinematic PPP coordinates obtained at the stations on the anomaly days were examined. The results showed that the degradation level of kinematic PPP solutions depends on the intensity of the TEC fluctuations. However, in cases the TEC anomaly is low, it has no significant effect on the positioning accuracy.

Bu çalışmada 2021 yılına ait bir yıllık periyodu içeren son, hızlı ve ultra hızlı yörünge (sp3) ve saat dosyalarının GPS, GLONASS, Galileo, Beidou-2, BeiDou-3 ve QZSS uydu sayısı doluluk analizleri ücretsiz yayınlanan bütün analiz merkezleri için gerçekleştirilmiştir. Ayrıca yörünge dosyasında mevcut olmayan uydu saat hatalarının oranı da bütün analiz merkezleri için hesaplanmıştır. Yapılan analizler sonucunda, GPS ve GLONASS uydu sayılarının analiz merkezleri arasında önemli oranda değişmediği, Galileo ve BeiDou uydu sayılarının ise analiz merkezleri arasında önemli değişiklikler gösterdiği görülmüştür. En az Galileo uydu sayısı son, hızlı ve ultra-hızlı yörünge ürünleri için sırası ile CNES (son), GFZ (hızlı) ve GFZ (ultra) analiz merkezlerinden elde edilmiştir. BeiDou-3 (MEO) ve QZSS uyduları için en az uydu sayısı son yörünge dosyaları içinden CODE analiz merkezi için hesaplanmıştır.

Precise point positioning with ambiguity resolution (PPP-AR) is a powerful tool for geodetic and time-constrained applications that require high precision. The performance of PPP-AR highly depends on the reliability of the correct integer carrier-phase ambiguity estimation. In this study, the performance of narrow-lane ambiguity resolution of PPP using the Least-squares AMBiguity Decorrelation (LAMBDA) and bootstrapping methods is extensively investigated using real data from 55 IGS stations over one-month in 2020. Static PPP with 24-, 12-, 8-, 4-, 2-, 1- and ½-h sessions using two different cutoff angles (7° and 30°) was conducted with three PPP modes: i.e. ambiguity-float and two kinds of ambiguity-fixed PPP using the LAMBDA and bootstrapping methods for narrow-lane AR, respectively. The results show that the LAMBDA method can produce more reliable results for 2 hour and shorter observation sessions compared with the bootstrapping method using a 7° cutoff angle. For a 30° cutoff angle, the LAMBDA method outperforms the bootstrapping method for observation sessions of 4 h and less. For long observation times, the bootstrapping method produced much more accurate coordinates compared with the LAMBDA method without considering the wrong fixes cases. The results also show that occurrences of fixing the wrong integer ambiguities using the bootstrapping method are higher than that of the LAMBDA method.

The Precise Point Positioning technique (PPP), which emerged as an alternative to the conventional relative positioning method, has been widely used in many applications in recent years. The PPP method is a special case of absolute positioning method, in this method the static and kinematic position can be determined with high accuracy by using single GNSS receiver. On the other hand, thanks to the real-time precise orbit and clock products made available by different establishments and organizations (International GNSS Service-IGS, Federal Agency for Cartography and Geodesy-BKG, European Space Agency-ESA, European Reference Frame-EUREF, German Research Centre for Geosciences-GFZ etc.), PPP method has started to be used in applications that require real-time position information. The high interest in this method, which is called real-time-PPP (RT-PPP), has accelerated the development of the method. Many software have been developed in this context. In this study, the positioning performance of RT-PPP method was investigated using BKG/BNC (BKG Ntrip Client), RTKLIB/RTKNAVI (Real Time Kinematic Library) and PPP-WIZARD (PPP With Integer and Zero-difference Ambiguity Resolution Demonstrator) software. For this purpose, real time coordinate values of ISTA IGS station, located in Istanbul, belongs to the observation period of about 25 hours were obtained in 1 second epoch interval. The obtained results were compared with the reference coordinates of the station, and examined in terms of accuracy and precision. According to the results, it has been observed that the convergence time sometimes exceeds 1 hour, and after this time, an accuracy of approximately +/- 10 cm in horizontal component and +/- 20 cm in vertical component could be obtained with BKG/BNC and RTKLIB/RTKNAVI. However the accuracy of the coordinates obtained using the PPP-WIZARD software is over +/- 30 cm due to the large number of disconnections and subsequent convergence.

Göreli konum belirleme yöntemine alternatif olarak ortaya çıkan Hassas Nokta Konum Belirleme (PPP) yöntemi son yıllarda yaygın olarak kullanılmaktadır. PPP yöntemi mutlak konum belirleme yönteminin özel bir durumu olup, bu yöntem ile tam sayı belirsizlik çözümündeki ilerleme sayesinde tek bir GNSS alıcısı kullanılarak yüksek doğruluklu konum bilgisi elde edilebilmektedir. Son birkaç yılda ise farklı servislerin (IGS, BKG, ESA, EUREF, GFZ vb.) sunduğu gerçek zamanlı düzeltme bilgisi ve ürünleri sayesinde PPP yöntemi gerçek zamanlı olarak (RT-PPP) kullanılmaya başlamıştır. RT-PPP’ ye olan ilginin oldukça yüksek olması yöntemin gelişimine hız katmıştır. Bu bağlamda birçok yazılım üretilmiştir. Bu çalışmada, bu yazılımlardan BKG/BNC, RTKLIB/RTKNAVI, PPP-WIZARD kullanılarak, RT-PPP yönteminin konum belirleme performansı test edilmiştir. Bu amaçla ISTA IGS/RTS istasyonuna ait gerçek zamanlı koordinat değerleri 1 saniye epok aralığında elde edilmiştir. Elde edilen sonuçlar doğruluk ve hassasiyet bakımından incelenmiştir. Sonuçlara göre, yakınsama süresi göz ardı edildiğinde BKG/BNC ve RTKLIB/RTKNAVI ile yatay bileşende genellikle ± 10 cm, düşey bileşende ise ± 20 cm gibi bir doğruluğun elde edilebildiği görülmüştür. Ancak PPP-WIZARD yazılımı kullanılarak elde edilen koordinatların doğruluğu oldukça düşüktür.