# Property Analysis of the Real-Time Uncalibrated Phase Delay Product Generated by Regional Reference Stations and Its Influence on Precise Point Positioning Ambiguity Resolution

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## Abstract

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## 1. Introduction

## 2. RTPPP-AR and RT UPD Estimation

#### 2.1. RTPPP-AR Method

#### 2.2. UPD Real-Time Estimation for Satellite Terminal

## 3. Experiment Results and Discussion

#### 3.1. Real-Time Uncorrected Phase Delay UPD Characteristic of Satellite Terminal

#### 3.2. UPD Estimated by Regional Stations for RTPPP-AR Positioning Experiments

## 4. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## References

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**Figure 3.**The fractional values of the wide lane ambiguity of G06 (reference satellite G02) at different stations.

**Figure 4.**GPS satellite wide-lane ambiguity and number of single-difference ambiguities for calculation.

**Figure 5.**Wide-lane uncalibrated phase delay of the GPS satellite between the 187th and the 206th day of 2016.

**Figure 6.**Narrow-lane uncalibrated phase delay of the GPS satellite between the 187th and the 193th day of 2016.

**Figure 9.**RTPPP-AR average percentage ambiguity fixed rates of different regional stations in different UPD models (reference station coordinates are set to known).

**Figure 10.**Average TTFF for RTPPP-AR of different regional stations in different UPD models (reference station coordinates are set to known).

**Table 1.**Wide-lane uncalibrated phase delay STD of the GPS satellite between the 187th and the 206th day of 2016.

PRN | G02 | G03 | G06 | G09 | G12 | G19 | G23 | G28 |
---|---|---|---|---|---|---|---|---|

STD [cycles] | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.02 | 0.02 | 0.02 |

STD [m] | 0.026 | 0.026 | 0.026 | 0.026 | 0.026 | 0.017 | 0.017 | 0.017 |

**Table 2.**Narrow-lane uncalibrated phase delay STD of the GPS satellite between the 187th and the 193th day of 2016.

PRN | G03 | G06 | G09 | G19 | G23 | G28 |
---|---|---|---|---|---|---|

STD [cycles] | 0.32 | 0.12 | 0.31 | 0.24 | 0.17 | 0.27 |

STD [m] | 0.034 | 0.013 | 0.032 | 0.026 | 0.018 | 0.029 |

Model | Stations for UPD Estimation | Strategy Information |
---|---|---|

Model 1: ALL Sites UPD Model | 37 stations in total | All 37 stations were adopted for UPD estimation, and the UPD results were adopted for RTPPP-AR calculation of all stations. |

Model 2: Shanghai UPD Model | YIWU, XUCH, CJZZ, DING, DPZZ, FUQI, JD01, JSWZ, JZZZ, LJIN, LNGN, XTZZ, ZQZZ (14 stations) | 14 stations in Shanghai regions were adopted for UPD estimation, and the UPD results were adopted for RTPPP-AR calculation of all stations. |

Model 3: Hong Kong UPD Model | HKKS, HKKT, HKLM, HKMW, HKNP, HKOH, HKPC, HKSC, HKSL, HKSS, HKST, HKTK, HKWS (13 stations) | 13 stations in Hong Kong were adopted for UPD estimation, and the UPD results were adopted for RTPPP-AR calculation of all stations. |

**Table 4.**Percentage of epoch ambiguity fixed rates for RTPPP-AR of Different Regional Stations in Different UPD Models (reference station coordinates are set to known).

Station | Model | Station | Model | Station | Model | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|

1 | 2 | 3 | 1 | 2 | 3 | 1 | 2 | 3 | |||

YIWU | 95.6 | 90.3 | 80.9 | HKKS | 92.3 | 69.2 | 98.9 | SZ01 | 85.8 | 52.8 | 52.5 |

XUCH | 87.8 | 75.8 | 59.1 | HKKT | 98.8 | 74.0 | 99.0 | TG01 | 88.0 | 46.1 | 57.6 |

CJZZ | 91.3 | 93.3 | 74.2 | HKLM | 99.1 | 83.3 | 99.8 | TGT0 | 80.7 | 57.0 | 56.8 |

DING | 89.9 | 84.6 | 55.9 | HKMW | 91.0 | 63.3 | 98.8 | TP01 | 86.6 | 68.8 | 56.0 |

DPZZ | 96.0 | 96.4 | 75.9 | HKNP | 99.2 | 78.0 | 99.2 | WK01 | 73.6 | 46.7 | 47.5 |

FUQI | 77.1 | 86.2 | 23.3 | HKOH | 98.7 | 64.1 | 99.0 | XLH0 | 86.5 | 62.8 | 51.4 |

JD01 | 92.8 | 92.3 | 56.9 | HKPC | 99.3 | 70.3 | 99.6 | XQ01 | 61.1 | 39.7 | 35.7 |

JSWZ | 92.8 | 93.4 | 76.3 | HKSC | 99.3 | 73.7 | 99.8 | XY01 | 83.4 | 65.9 | 76.2 |

JZZZ | 96.2 | 93.3 | 88.3 | HKSL | 99.2 | 56.8 | 99.8 | YL01 | 81.7 | 69.3 | 57.5 |

LJIN | 96.8 | 92.8 | 49.0 | HKSS | 99.1 | 65.0 | 99.3 | BD01 | 60.7 | 28.6 | 28.4 |

XTZZ | 96.3 | 92.7 | 93.7 | HKST | 99.0 | 69.8 | 99.4 | DG01 | 90.4 | 66.5 | 50.6 |

ZQZZ | 97.0 | 82.6 | 79.2 | HKTK | 98.0 | 72.9 | 99.1 | ||||

HKWS | 99.4 | 71.5 | 99.4 | ||||||||

Average | 92.5 | 89.48 | 67.7 | Average | 97.9 | 70.2 | 99.3 | Average | 79.9 | 42.9 | 55.8 |

Stations in Shanghai, etc. (SH Sites) | Stations in Hong Kong (HK Sites) | Stations in Tianjin (QD Sites) |

**Table 5.**TTFF for RTPPP-AR of different regional stations in different UPD models (reference station coordinates are set to known).

Station | Model | Station | Model | Station | Model | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|

1 | 2 | 3 | 1 | 2 | 3 | 1 | 2 | 3 | |||

YIWU | 26 | 1 | 79 | HKKS | 1 | 92 | 1 | SZ01 | 1 | 42 | 37 |

XUCH | 2 | 14 | 89 | HKKT | 1 | 12 | 2 | TG01 | 3 | 47 | 68 |

CJZZ | 17 | 15 | 51 | HKLM | 3 | 50 | 2 | TGT0 | 4 | 45 | 7 |

DING | 2 | 1 | 54 | HKMW | 13 | 84 | 11 | TP01 | 1 | 63 | 5 |

DPZZ | 1 | 9 | 33 | HKNP | 24 | 83 | 2 | WK01 | 17 | 26 | 24 |

FUQI | 7 | 5 | 29 | HKOH | 3 | 88 | 8 | XLH0 | 9 | 52 | 24 |

JD01 | 6 | 23 | 82 | HKPC | 5 | 84 | 3 | XQ01 | 1 | 49 | 3 |

JSWZ | 2 | 7 | 31 | HKSC | 1 | 15 | 1 | XY01 | 1 | 26 | 10 |

JZZZ | 2 | 3 | 36 | HKSL | 2 | 75 | 1 | YL01 | 1 | 46 | 11 |

LJIN | 1 | 8 | 34 | HKSS | 1 | 82 | 1 | BD01 | 2 | 21 | 26 |

XTZZ | 2 | 5 | 35 | HKST | 12 | 23 | 10 | DG01 | 1 | 50 | 18 |

ZQZZ | 1 | 4 | 25 | HKTK | 1 | 86 | 1 | ||||

HKWS | 1 | 6 | 1 | ||||||||

Average | 5.8 | 7.9 | 48.2 | Average | 5.6 | 57.3 | 3.6 | Average | 3.7 | 42.5 | 21.2 |

Stations in Shanghai, etc. (SH Sites) | Stations in Hong Kong (HK Sites) | Stations in Tianjin (QD Sites) |

**Table 6.**Statistical sheet for RTPPP-AR positioning accuracies of different regional stations in different models.

Regional Station | Bias [m] | MODEL 1 | MODEL 2 | MODEL 3 | Average [m] |
---|---|---|---|---|---|

SH Sites | N | 0.022 | 0.021 | 0.024 | 0.022 |

E | 0.016 | 0.016 | 0.017 | 0.016 | |

U | 0.059 | 0.056 | 0.058 | 0.058 | |

HK Sites | N | 0.038 | 0.037 | 0.036 | 0.037 |

E | 0.026 | 0.031 | 0.027 | 0.028 | |

U | 0.078 | 0.077 | 0.083 | 0.079 | |

QD Sites | N | 0.026 | 0.024 | 0.023 | 0.024 |

E | 0.018 | 0.018 | 0.017 | 0.018 | |

U | 0.055 | 0.049 | 0.059 | 0.054 |

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**MDPI and ACS Style**

Zhang, Y.; Wang, Q.; Jiang, X.
Property Analysis of the Real-Time Uncalibrated Phase Delay Product Generated by Regional Reference Stations and Its Influence on Precise Point Positioning Ambiguity Resolution. *Sensors* **2017**, *17*, 1162.
https://doi.org/10.3390/s17051162

**AMA Style**

Zhang Y, Wang Q, Jiang X.
Property Analysis of the Real-Time Uncalibrated Phase Delay Product Generated by Regional Reference Stations and Its Influence on Precise Point Positioning Ambiguity Resolution. *Sensors*. 2017; 17(5):1162.
https://doi.org/10.3390/s17051162

**Chicago/Turabian Style**

Zhang, Yong, Qing Wang, and Xinyuan Jiang.
2017. "Property Analysis of the Real-Time Uncalibrated Phase Delay Product Generated by Regional Reference Stations and Its Influence on Precise Point Positioning Ambiguity Resolution" *Sensors* 17, no. 5: 1162.
https://doi.org/10.3390/s17051162