Weighting of Multi-GNSS Observations in Real-Time Precise Point Positioning

The update of the Android system and the emergence of the dual-frequency GNSS chips enable smartphones to acquire dual-frequency GNSS observations. In this paper, the GPS L1/L5 and Galileo E1/E5a dual-frequency PPP (precise point positioning) algorithm based on RTKLIB and GAMP was applied to analyze the positioning performance of the Xiaomi Mi 8 dual-frequency smartphone in static and kinematic modes. The results showed that in the static mode, the RMS position errors of the dual-frequency smartphone PPP solutions in the E, N, and U directions were 21.8 cm, 4.1 cm, and 11.0 cm, respectively, after convergence to 1 m within 102 min. The PPP of dual-frequency smartphone showed similar accuracy with geodetic receiver in single-frequency mode, while geodetic receiver in dual-frequency mode has higher accuracy. In the kinematic mode, the positioning track of the smartphone dual-frequency data had severe fluctuations, the positioning tracks derived from the smartphone and the geodetic receiver showed approximately difference of 3–5 m.

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Simulation case study of deformations and landslides using real-time GNSS precise point positioning technique

Geomatics Natural Hazards and Risk ◽

10.1080/19475705.2015.1137243 ◽

2016 ◽

Vol 7 (6) ◽

pp. 1856-1873 ◽

Cited By ~ 6

Author(s):

Raquel M. Capilla ◽

José Luis Berné ◽

Angel Martín ◽

Raul Rodrigo

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Positioning Technique ◽

Point Positioning

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Precise Point Positioning Using the Regional BeiDou Navigation Satellite Constellation

Journal of Navigation ◽

10.1017/s0373463313000842 ◽

2014 ◽

Vol 67 (3) ◽

pp. 523-537 ◽

Cited By ~ 7

Author(s):

Aigong Xu ◽

Zongqiu Xu ◽

Xinchao Xu ◽

Huizhong Zhu ◽

Xin Sui ◽

...

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Satellite System ◽

Convergence Time ◽

Asia Pacific ◽

Satellite Orbits ◽

Navigation Satellite ◽

Asia Pacific Region ◽

Point Positioning

On 27 December 2012 it was announced officially that the Chinese Navigation Satellite System BeiDou (BDS) was able to provide operational services over the Asia-Pacific region. The quality of BDS observations was confirmed as comparable with those of GPS, and relative positioning in static and kinematic modes were also demonstrated to be very promising. As Precise Point Positioning (PPP) technology is widely recognized as a method of precise positioning service, especially in real-time, in this contribution we concentrate on the PPP performance using BDS data only. BDS PPP in static, kinematic and simulated real-time kinematic mode is carried out for a regional network with six stations equipped with GPS- and BDS-capable receivers, using precise satellite orbits and clocks estimated from a global BDS tracking network. To validate the derived positions and trajectories, they are compared to the daily PPP solution using GPS data. The assessment confirms that the performance of BDS PPP is very comparable with GPS in terms of both convergence time and accuracy.

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DAY BY DAY BEHAVIOR OF GNNS POSITIONING ERRORS AND TEC FLUCTUATIONS ASSOCIATED AURORAL DISTURBANCES OVER MARCH 2015

PHYSICS OF AURORAL PHENOMENA ◽

10.51981/2588-0039.2021.44.005 ◽

2021 ◽

Vol 44 ◽

pp. 24-27

Author(s):

I.I. Efishov ◽

◽

I.I. Shagimuratov ◽

I.E. Zakharenkova ◽

N.Yu. Tepenitsyna ◽

...

Keyword(s):

Precise Point Positioning ◽

Efficient Computation ◽

Gps Measurements ◽

Auroral Activity ◽

Positioning Errors ◽

Point Positioning ◽

European Sector ◽

Day By Day ◽

Single Receiver ◽

Gnss Observations

We analyzed the occurrence of TEC fluctuations and an impact of auroral disturbances on the Precise Point Positioning (PPP) errors in European sector using GPS measurements of EPN network. Index AE was used as indicator of auroral activity. The fluctuation activity was evaluated by indexes ROT and ROTI. The positioning errors were determined using the GIPSY-OASIS software (http://apps.gdgps.net). The Precise Point Positioning is the processing strategy of the single receiver for GNSS observations that enables the efficient computation of the high-quality coordinates. For quiet conditions the algorithm provided for TRO1 stations daily average PPP errors less than 4-5 sm. The analysis indicated regular increasing positioning errors around MLT (22 UT) during March 2015. While raising the auroral activity it was observed increasing TEC fluctuation as well as positioning errors. In the report we discus also behavior PPP errors during super storm 17 March 2015. During storm at TRO1 the PPP errors reached more than 20 m. The increasing errors were observed on latitudes low than 52-54°N.

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Examining the Accuracy of Network RTK and Long Base RTK Methods with Repetitive Measurements

Journal of Sensors ◽

10.1155/2019/3572605 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Tamer Baybura ◽

İbrahim Tiryakioğlu ◽

Mehmet Ali Uğur ◽

Halil İbrahim Solak ◽

Şeyma Şafak

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

High Accuracy ◽

Base Station ◽

Network Rtk ◽

Real Time Kinematic ◽

Study Results ◽

Point Positioning

Real-time kinematic (RTK) technique is important for mapping applications requiring short measure time, the distance between rover and base station, and high accuracy. There are several RTK methods used today such as the traditional RTK, long base RTK (LBRTK), network RTK (NRTK), and precise point positioning RTK (PPP-RTK). NRTK and LBRTK are popular with the advantage of the distance, the time, and accuracy. In the present study, the NRTK and LBRTK measurements were compared in terms of accuracy and distance in a test network with 6 sites that was established between 5 and 60 km. Repetitive NRTK and LBRTK measurements were performed on 6 different days in 2015-2017-2018 and additionally 4 campaigns of repetitive static measurements were carried out in this test network. The results of NRTK and LBRTK methods were examined and compared with all relevant aspects by considering the results of the static measurements as real coordinates. The study results showed that the LBRTK and NRTK methods yielded similar results at base lengths up to 40 km with the differences less than 3 cm horizontally and 4 cm vertically.

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Enhancing real-time precise point positioning time and frequency transfer with receiver clock modeling

GPS Solutions ◽

10.1007/s10291-018-0814-y ◽

2018 ◽

Vol 23 (1) ◽

Cited By ~ 14

Author(s):

Yulong Ge ◽

Feng Zhou ◽

Tianjun Liu ◽

WeiJin Qin ◽

Shengli Wang ◽

...

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Receiver Clock ◽

Frequency Transfer ◽

Point Positioning ◽

Positioning Time

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Performance of Real-Time Precise Point Positioning

Marine Geodesy ◽

10.1080/01490419.2012.699503 ◽

2013 ◽

Vol 36 (1) ◽

pp. 98-108 ◽

Cited By ~ 23

Author(s):

Junping Chen ◽

Haojun Li ◽

Bin Wu ◽

Yize Zhang ◽

Jiexian Wang ◽

...

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Point Positioning

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GPS inter-frequency clock bias modeling and prediction for real-time precise point positioning

GPS Solutions ◽

10.1007/s10291-018-0741-y ◽

2018 ◽

Vol 22 (3) ◽

Cited By ~ 13

Author(s):

Lin Pan ◽

Xiaohong Zhang ◽

Xingxing Li ◽

Jingnan Liu ◽

Fei Guo ◽

...

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Modeling And Prediction ◽

Point Positioning

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Real-Time Precise Point Positioning Using Orbit and Clock Corrections as Quasi-Observations for Improved Detection of Faults

Journal of Navigation ◽

10.1017/s0373463317001023 ◽

2018 ◽

Vol 71 (4) ◽

pp. 769-787 ◽

Cited By ~ 7

Author(s):

Ahmed El-Mowafy

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Exclusion Process ◽

Satellite Orbit ◽

Satellite System ◽

Navigation Satellite ◽

System Service ◽

Point Positioning ◽

Predicted Values ◽

Global Navigation Satellite

Real-time Precise Point Positioning (PPP) relies on the use of accurate satellite orbit and clock corrections. If these corrections contain large errors or faults, either from the system or by meaconing, they will adversely affect positioning. Therefore, such faults have to be detected and excluded. In traditional PPP, measurements that have faulty corrections are typically excluded as they are merged together. In this contribution, a new PPP model that encompasses the orbit and clock corrections as quasi-observations is presented such that they undergo the fault detection and exclusion process separate from the observations. This enables the use of measurements that have faulty corrections along with predicted values of these corrections in place of the excluded ones. Moreover, the proposed approach allows for inclusion of the complete stochastic information of the corrections. To facilitate modelling of the orbit and clock corrections as quasi-observations, International Global Navigation Satellite System Service (IGS) real-time corrections were characterised over a six-month period. The proposed method is validated and its benefits are demonstrated at two sites using three days of data.

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