Research on presice point positioning and Real-Time Kinematics corrections for unmanned aerial vehicle global positioning systems

Unmanned Aerial Vehicles (UAVs) are used in different tasks with different flight path accuracy. To achieve a greater accuracy of flight trajectory GPS accuracy improvement methods are analyzed. The present article explains the main principles of GPS measurement. Precise Point Positioning (PPP) and Real-Time Kinematics (RTK) methods are described. and compared. Also, both methods have been tested.

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Performance Evaluation of Kinematic BDS/GNSS Real-Time Precise Point Positioning for Maritime Positioning

Journal of Navigation ◽

10.1017/s0373463318000644 ◽

2018 ◽

Vol 72 (1) ◽

pp. 34-52 ◽

Cited By ~ 6

Author(s):

Fuxin Yang ◽

Lin Zhao ◽

Liang Li ◽

Shaojun Feng ◽

Jianhua Cheng

Keyword(s):

Real Time ◽

Precise Point Positioning ◽

Cost Effective ◽

Satellite System ◽

Convergence Time ◽

Kinematic Data ◽

Position Accuracy ◽

Global Positioning ◽

Cost Effective Technique ◽

Point Positioning

Real-time Precise Point Positioning (PPP) has been evolved as a cost-effective technique for highly precise maritime positioning. For a long period, maritime PPP technology has mainly relied on the Global Positioning System (GPS). With the revitalisation of GLONASS and the emerging BeiDou navigation satellite system (BDS), it is now feasible to investigate real-time navigation performance of multi-constellation maritime PPP with GPS, BDS and GLONASS. In this contribution, we focus on maritime PPP performance using real world maritime kinematic data and real-time satellite correction products. The results show that BDS has lower position accuracy and slower convergence time than GPS. The BDS and GPS combination has the best performance among the dual-constellation configurations. Meanwhile, the integration of BDS, GLONASS and GPS significantly improves the position accuracy and the convergence time. Some outliers in the single constellation configuration can be mitigated when multi-constellation observations are utilised.

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Ambiguity of Residual Constraint-Based Precise Point Positioning with Partial Ambiguity Resolution under No Real-Time Network Corrections Using Real Global Positioning System (GPS) Data

Sensors ◽

10.3390/s20113220 ◽

2020 ◽

Vol 20 (11) ◽

pp. 3220

Author(s):

Honglei Qin ◽

Peng Liu ◽

Li Cong ◽

Xia Xue

Keyword(s):

Real Time ◽

Global Positioning System ◽

Ambiguity Resolution ◽

Precise Point Positioning ◽

Convergence Time ◽

Positioning System ◽

Post Processing ◽

Partial Ambiguity Resolution ◽

Global Positioning ◽

Point Positioning

Although precise point positioning (PPP) is a well-established and promising technique with the use of precise satellite orbit and clock products, it costs a long convergence time to reach a centimeter-level positioning accuracy. The PPP with ambiguity resolution (PPP-AR) technique can improve convergence performance by resolving ambiguities after separating the fractional cycle bias (FCB). Now the FCB estimation is mainly realized by the regional or global operating reference station network. However, it does not work well in the areas where network resources are scarce. The contribution of this paper is to realize an ambiguity residual constraint-based PPP with partial ambiguity resolution (PPP-PARC) under no real-time network corrections to speed up the convergence, especially when the performance of the float solution is poor. More specifically, the update strategy of FCB estimation in a stand-alone receiver is proposed to realize the PPP-PAR. Thereafter, the solving process of FCB in a stand-alone receiver is summarized. Meanwhile, the influencing factors of the ambiguity success rate in the PPP-PAR without network corrections are analyzed. Meanwhile, the ambiguity residual constraint is added to adapt the particularity of the partial ambiguity-fixing without network corrections. Moreover, the positioning experiments with raw observation data at the Global Positioning System (GPS) globally distributed reference stations are conducted to determine the ambiguity residual threshold for post-processing and real-time scenarios. Finally, the positioning performance was verified by 22 GPS reference stations. The results show that convergence time is reduced by 15.8% and 26.4% in post-processing and real-time scenarios, respectively, when the float solution is unstable, compared with PPP using a float solution. However, if the float solution is stable, the PPP-PARC method has performance similar to the float solution. The method shows the significance of the PPP-PARC for future PPP applications in areas where network resource is deficient.

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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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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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