# Comparison Analysis on the Accuracy of Galileo PPP Using Different Frequency Combinations in Europe

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## Abstract

**:**

## 1. Introduction

## 2. Methods

## 3. Experiments and Results

#### 3.1. Processing Strategies

#### 3.2. Evaluation of the Accuracy of Dual-Frequency Galileo Static PPP

#### 3.3. Evaluation of the Accuracy of Dual- and Triple-Frequency Galileo Static PPP

#### 3.4. Accuracy of Multi-Frequency Galileo Kinematic PPP

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Number of observed satellites and the global dilution of position (GDOP) for GPS and GAL on station SKE8 on DOY 120, 2020.

**Figure 2.**The RMS on north (

**top**), east (

**middle**), and up (

**bottom**) components for GPS (

**left**), and its comparison with the GAL dual-frequency static PPP (

**right**).

**Figure 4.**The RMS on north (

**top**), east (

**middle**), and up (

**bottom**) component for GPS (

**left**), and its comparison to the BDS dual-frequency PPP.

**Figure 11.**PCR at “S10” (

**top**) and “S20” (

**bottom**) for different receivers using GPS + Galileo dual-frequency PPP.

Model | Settings |
---|---|

Sample rate | 30 s |

Elevation cutoff angle | 7° |

Phase wind-up | Phase wind-up correction |

Satellite and receiver antenna phase center | Using igs14_2101.atx |

Relativity | Corrected |

Satellite attitude model | Yaw-Steering |

Satellite orbit/clock | Corrected with GFZ multi-GNSS final products |

DCBs | Corrected with products provided by DLR |

Earth tides correction | IERS2010 |

Station coordinates | Estimated as static and kinematic |

Troposphere | ZHD: Saastamoinen model [21] ZWD: Estimated as the random walk process parameter for each station Mapping function: Niell mapping function |

Receiver clocks | Solved for at each epoch as white noise |

Inter frequency bias (IFB) | Modeled as constant |

Filter method | Kalman filter |

Receiver Type | Antenna Type | Stations |
---|---|---|

TRIMBLE NETR9 | LEIAR25.R3 LEIT | ARJ6 JON6 KAD6 LOV6 NOR7 OSK6 OST6 OVE6 SKE8 LEK6 |

JAVAD TRE_3 DELTA | JAVRINGANT_DM SCIS | KEV2 KIV2 KILP FINS JOE2 OLK2 OUL2 ROM2 SAVU |

Group | Strategies |
---|---|

GPS-IF | L1/L2 IF PPP |

BDS-IF | B1/B3 IF PPP |

GAL-IF | E1/E5a IF PPP |

GAL-R15 | E1/E5a RAW PPP |

GAL-R17 | E1/E5b RAW PPP |

GAL-R18 | E1/E5 RAW PPP |

GAL-R157 | E1/E5a/E5b RAW PPP |

GAL-R1578 | E1/E5a/E5b/E5 RAW PPP |

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**MDPI and ACS Style**

Song, J.; Zhao, L.
Comparison Analysis on the Accuracy of Galileo PPP Using Different Frequency Combinations in Europe. *Appl. Sci.* **2021**, *11*, 10020.
https://doi.org/10.3390/app112110020

**AMA Style**

Song J, Zhao L.
Comparison Analysis on the Accuracy of Galileo PPP Using Different Frequency Combinations in Europe. *Applied Sciences*. 2021; 11(21):10020.
https://doi.org/10.3390/app112110020

**Chicago/Turabian Style**

Song, Jia, and Lewen Zhao.
2021. "Comparison Analysis on the Accuracy of Galileo PPP Using Different Frequency Combinations in Europe" *Applied Sciences* 11, no. 21: 10020.
https://doi.org/10.3390/app112110020