scholarly journals Analysis of the BDGIM Performance in BDS Single Point Positioning

2021 ◽  
Vol 13 (19) ◽  
pp. 3888
Author(s):  
Guangxing Wang ◽  
Zhihao Yin ◽  
Zhigang Hu ◽  
Gang Chen ◽  
Wei Li ◽  
...  
Keyword(s):  
Geomagnetic Storm ◽  
High Latitude ◽  
Single Point ◽  
Ionospheric Model ◽  
Winter Solstice ◽  
Positioning Accuracy ◽  
Single Point Positioning ◽  
Klobuchar Model ◽  
3D Positioning ◽  
Better Than

The broadcast ionospheric model is mainly used to correct the ionospheric delay error for single-frequency users. Since the BeiDou global ionospheric delay correction model (BDGIM) is a novel broadcast ionospheric model for BDS-3, its performance was analyzed through single point positioning (SPP) in this study. Twenty-two stations simultaneously receiving B1C, B2a, B1I and B3I signals were selected from the International GNSS Service (IGS) and the International GNSS Monitoring and Assessment System (iGMAS) tracking networks for the SPP experiments. The differential code bias (DCB) parameters were used to correct the hardware delays in the signals of B1C and B2a. The results showed that the BDGIM performs the best in high-latitude areas, and can effectively improve the positioning accuracy compared with the Klobuchar model. The average 3D positioning accuracy of the four civil signals can reach 3.58 m in high-latitude areas. The positioning accuracies with the BDGIM in the northern hemisphere are better than those in the southern hemisphere, and the global average 3D positioning accuracy of the four civil signals is 4.60 m. The performance of the BDGIM also shows some seasonal differences. The BDGIM performs better than the Klobuchar model on the days of spring equinox and winter solstice, while the opposite is true on the days of summer solstice and autumn equinox. On the day of winter solstice, the average 3D accuracies with the BDGIM on the signals of B1C, B2a, B1I and B3I are 4.13 m, 5.32 m, 4.40 m and 4.49 m, respectively. Although the SPP accuracies are to some extent affected by the geomagnetic storm, the BDGIM generally performs better and are more resistant to the geomagnetic storm than the Klobuchar model.

On the improvements of the single point positioning accuracy with Locata technology

GPS Solutions ◽  
2013 ◽  
Vol 18 (2) ◽  
pp. 273-282 ◽  
Author(s):  
Jean-Philippe Montillet ◽  
Lukasz K. Bonenberg ◽  
Craig M. Hancock ◽  
Gethin W. Roberts
Keyword(s):  
Single Point ◽  
Positioning Accuracy ◽  
Single Point Positioning ◽  
Point Positioning

scholarly journals Bidirectional Sliding Window for Boundary Recognition of Pavement Construction Area Using GPS-RTK

2020 ◽  
Vol 10 (4) ◽  
pp. 1277 ◽  
Author(s):  
Tong Xu ◽  
Siwei Chen ◽  
Dong Wang ◽  
Weigong Zhang
Keyword(s):  
Single Point ◽  
Sliding Window ◽  
Straight Line Segment ◽  
Distribution Models ◽  
Positioning Accuracy ◽  
Single Point Positioning ◽  
Boundary Recognition ◽  
Gps Rtk ◽  
Point Positioning ◽  
Pavement Construction

Unmanned pavement construction is of great significance in China, and the primary issue to be solved is how to identify the boundaries of the Pavement Construction Area (PCA). In this paper, we present a simple yet effective method, named the Bidirectional Sliding Window (BSW) method, for PCA boundary recognition. We first collected the latitude and longitude coordinates of the four vertices of straight quadrilaterals using the Global Positioning System—Real Time Kinematic (GPS-RTK) measurement principle for precise single-point positioning, analyzed single-point positioning accuracy, and determined the measurement error distribution models. Next, we took points at equal intervals along one straight line segment and two curved line segments with curvature radii of 70 m to 300 m, for simulation experiments. BSW was adopted to recognize the Possible Irrelevant Points (PIP) and Relevant Points (RP), which were used to identify PCA boundaries. Experiments show that when the proposed BSW algorithm is used and the single-point positioning accuracy is at the centimeter level, PCA boundary recognition for straight polygons reaches single-point positioning accuracy, and that for curved polygons reaches decimeter-level accuracy.

scholarly journals Smartphone Positioning and Accuracy Analysis Based on Real-Time Regional Ionospheric Correction Model

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3879
Author(s):  
Qi Liu ◽  
Chengfa Gao ◽  
Zihan Peng ◽  
Ruicheng Zhang ◽  
Rui Shang
Keyword(s):  
Real Time ◽  
Convergence Time ◽  
Electron Content ◽  
Ionospheric Model ◽  
Positioning Accuracy ◽  
Correction Model ◽  
The Real ◽  
Gnss Positioning ◽  
Klobuchar Model ◽  
Regional Ionospheric Model

As one of the main errors that affects Global Navigation Satellite System (GNSS) positioning accuracy, ionospheric delay also affects the improvement of smartphone positioning accuracy. The current ionospheric error correction model used in smartphones has a certain time delay and low accuracy, which is difficult to meet the needs of real-time positioning of smartphones. This article proposes a method to use the real-time regional ionospheric model retrieved from the regional Continuously Operating Reference Stations (CORS) observation data to correct the GNSS positioning error of the smartphone. To verify the accuracy of the model, using the posterior grid as the standard, the electron content error of the regional ionospheric model is less than 5 Total Electron Content Unit (TECU), which is about 50% higher than the Klobuchar model, and to further evaluate the impact of the regional ionosphere model on the real-time positioning accuracy of smartphones, carrier-smoothing pseudorange and single-frequency Precise Point Positioning (PPP) tests were carried out. The results show that the real-time regional ionospheric model can significantly improve the positioning accuracy of smartphones, especially in the elevation direction. Compared with the Klobuchar model, the improvement effect is more than 34%, and the real-time regional ionospheric model also shortens the convergence time of the elevation direction to 1 min. (The convergence condition is that the range of continuous 20 s is less than 0.5 m).

scholarly journals Benefit of the NeQuick Galileo Version in GNSS Single-Point Positioning

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Antonio Angrisano ◽  
Salvatore Gaglione ◽  
Ciro Gioia ◽  
Marco Massaro ◽  
Salvatore Troisi
Keyword(s):  
Single Point ◽  
Three Dimensional ◽  
Signal Propagation ◽  
Maximum Error ◽  
Theoretical Physics ◽  
Single Frequency ◽  
Ionospheric Model ◽  
Single Point Positioning ◽  
Complex Architectures ◽  
Point Positioning

The GNSS measurements are strongly affected by ionospheric effects, due to the signal propagation through ionosphere; these effects could severely degrade the position; hence, a model to limit or remove the ionospheric error is necessary. The use of several techniques (DGPS, SBAS, and GBAS) reduces the ionospheric effect, but implies the use of expensive devices and/or complex architectures necessary to meet strong requirements in terms of accuracy and reliability for safety critical application. The cheapest and most widespread GNSS devices are single frequency stand-alone receivers able to partially correct this kind of error using suitable models. These algorithms compute the ionospheric delay starting from ionospheric model, which uses parameters broadcast within the navigation messages. NeQuick is a three-dimensional and time-dependent ionospheric model adopted by Galileo, the European GNSS, and developed by International Centre for Theoretical Physics (ICTP) together with Institute for Geophysics, Astrophysics, and Meteorology of the University of Graz. The aim of this paper is the performance assessment in single point positioning of the NeQuick Galileo version provided by ESA and the comparison with respect to the Klobuchar model used for GPS; the analysis is performed in position domain and the errors are examined in terms of RMS and maximum error for the horizontal and vertical components. A deep analysis is also provided for the application of the exanimated model in the first possible Galileo only position fix.

scholarly journals Effects of Canopy and Multi-Epoch Observations on Single-Point Positioning Errors of a GNSS in Coniferous and Broadleaved Forests

2021 ◽  
Vol 13 (12) ◽  
pp. 2325
Author(s):  
Tong Feng ◽  
Shilin Chen ◽  
Zhongke Feng ◽  
Chaoyong Shen ◽  
Yi Tian
Keyword(s):  
Single Point ◽  
Positioning Error ◽  
Forest Resource ◽  
Forest Types ◽  
Positioning Accuracy ◽  
Forest Model ◽  
Single Point Positioning ◽  
Positioning Errors ◽  
Point Positioning ◽  
Positioning Time

Global navigation satellite systems (GNSS) can quickly, efficiently, and accurately provide precise coordinates of points, lines, and surface elements, plus complete surveys and determine various boundary lines in forest investigations and management. The system has become a powerful tool for dynamic forest resource investigations and monitoring. GNSS technology plays a unique and important role in estimating timber volume, calculating timber cutting area, and determining the location of virgin forest roads and individual trees in forests. In this study, we quantitatively analyzed the influence of crown size and observation time on the single-point positioning accuracy of GNSS receivers for different forest types. The GNSS located single points for different forest types and crown sizes, enabling the collection of data. The locating time for each tree was more than 10 min. Statistical methods were used to analyze the positioning accuracy of multi-epoch data, and a model was developed to estimate the maximum positioning errors under different forest conditions in a certain positioning time. The results showed that for a continuous positioning time of approximately 10 min, the maximum positioning accuracies in coniferous and broadleaf forests were obtained, which were 12.13 and 15.11 m, respectively. The size of a single canopy had no obvious influence on the single-point positioning error of the GNSS, and canopy density was proven to be closely related to the positioning accuracy of a GNSS. The determination coefficients (R2) in the regression analysis of the general model, coniferous forest model, and broadleaved forest model that were developed in this study were 0.579, 0.701, and 0.544, respectively. These results indicated that the model could effectively predict the maximum positioning error in a certain period of time under different forest types and crown conditions at middle altitudes, which has important guiding significance for forest resource inventories and precise forest management.

Variations of Doppler results with software and time

1980 ◽  
Vol 294 (1410) ◽  
pp. 237-244
Keyword(s):  
Meteorological Parameters ◽  
Single Point ◽  
Good Balance ◽  
Single Point Positioning ◽  
True Value ◽  
Precise Ephemeris ◽  
Station Coordinates ◽  
Positioning Method ◽  
Point Positioning ◽  
Better Than

The variations of station coordinates deduced from Doppler observations with the use of a single point positioning method based on a precise ephemeris are estimated according to different models and softwares. An identical set of Doppler observations produces station coordinates whose coherence is generally better than 1 m. However, greater differences of 1.5 or 3 m can exceptionally be detected. Apart from the incoherence caused by the differences of models and criteria of data rejection, the reproducibility of Doppler results depends also, through the ephemeris used, on the epoch of measurements. From consecutive periods of 10 days of observations performed on the same site and analysed with the precise ephemeris computed by D. M. A., a set of station coordinates with a scatter of less than 1 m results. To keep the results near their true value it is also necessary to apply the model to a set of data having as characteristics a good balance between N-S and S-N passes, an approximate knowledge of the true meteorological parameters and at least 40 passes.

Sign in / Sign up

Export Citation Format

Share Document