# Performance Evaluation of Real-Time Precise Point Positioning with Both BDS-3 and BDS-2 Observations

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## Abstract

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## 1. Introduction

## 2. Real-Time BDS-3/BDS-2 PPP Model

## 3. Current Space Segment of BDS-3/BDS-2 Constellations

## 4. Results and Discussion

#### 4.1. Experimental Datasets

#### 4.2. Availability of BDS-3/BDS-2 Constellations

#### 4.3. Quality of BDS-3/BDS-2 Real-Time Precise Products

#### 4.4. Performance of Real-Time BDS-3/BDS-2 PPP

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Ground track of BDS-2 and BDS-3 satellites on day of the year (DOY) 140, 2020. Different colors in the figure refer to different satellites.

**Figure 3.**Global maps of the maximum, minimum and average number of visible satellites of GPS and BDS-3/BDS-2 on DOY 140–146 of 2020 (note that a visible satellite has an elevation angle higher than 7°).

**Figure 5.**Global maps of the maximum, minimum and average position dilution of precision (PDOP), values for BDS-3/BDS-2 and GPS on DOY 140–146 of 2020.

**Figure 8.**Radial errors of BDS-3/BDS-2 precise satellite orbits in the real-time situation. Different colors in the figure refer to different satellites.

**Figure 9.**Along-track errors of BDS-3/BDS-2 precise satellite orbits in the real-time situation. Different colors in the figure refer to different satellites.

**Figure 10.**Cross-track errors of BDS-3/BDS-2 precise satellite orbits in the real-time situation. Different colors in the figure refer to different satellites.

**Figure 11.**Errors of BDS-3/BDS-2 precise satellite clocks in the real-time situation. Different colors in the figure refer to different satellites.

**Figure 14.**Distribution of positioning accuracies from different static precise point positioning (PPP) solutions.

**Table 1.**Space segment of BeiDou navigation satellite system (BDS)-3 and BDS-2 as of September 2020.

Generation | Constellation | PRN |
---|---|---|

BDS-2 | GEO | C01–C05/(C18) |

IGSO | C06–C10/C13/C16 | |

MEO | C11/C12/C14 | |

BDS-3S | IGSO | (C31/C56) |

MEO | (C57/C58/C?) | |

BDS-3 | GEO | (C59–C61) |

IGSO | (C38–C40) | |

MEO | C19–C30/C32–C37/(C41–C46) |

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**MDPI and ACS Style**

Pan, L.; Li, X.; Yu, W.; Dai, W.; Kuang, C.; Chen, J.; Chen, F.; Xia, P. Performance Evaluation of Real-Time Precise Point Positioning with Both BDS-3 and BDS-2 Observations. *Sensors* **2020**, *20*, 6027.
https://doi.org/10.3390/s20216027

**AMA Style**

Pan L, Li X, Yu W, Dai W, Kuang C, Chen J, Chen F, Xia P. Performance Evaluation of Real-Time Precise Point Positioning with Both BDS-3 and BDS-2 Observations. *Sensors*. 2020; 20(21):6027.
https://doi.org/10.3390/s20216027

**Chicago/Turabian Style**

Pan, Lin, Xuanping Li, Wenkun Yu, Wujiao Dai, Cuilin Kuang, Jun Chen, Fade Chen, and Pengfei Xia. 2020. "Performance Evaluation of Real-Time Precise Point Positioning with Both BDS-3 and BDS-2 Observations" *Sensors* 20, no. 21: 6027.
https://doi.org/10.3390/s20216027