# Ellipse Coefficient Map-Based Geomagnetic Fingerprint Considering Azimuth Angles

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## Abstract

**:**

## 1. Introduction

## 2. Related Works

#### 2.1. Signal Characteristics of 3-Axis Geomagnetism

#### 2.2. Wi-Fi and Geomagnetic Fingerprint

## 3. Proposed ECM Based UFEE

#### 3.1. Proposed UFEE in the Training Phase

#### 3.2. The UFEE in Positioning Phase

## 4. Experiment Setup and Results

#### 4.1. Experiment Setup

#### 4.2. Experiment Results

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 10.**The acquired positioning frequencies of existing and proposed methods (

**a**) second floor; (

**b**) third floor; (

**c**) fourth floor.

**Figure 11.**Positioning results by MGIF and proposed UFEE as (

**a**) a confusion matrix of positioning at the second floor; (

**b**) a confusion matrix of positioning at the third floor; (

**c**) a confusion matrix of positioning at the fourth floor.

Floors | Accuracy (<1.5 m) | |
---|---|---|

MGIF [10] | Proposed UFEE | |

2F | 39.01% | 91.85% |

3F | 15.80% | 89.14% |

4F | 26.17% | 86.42% |

Average | 27.00% | 89.14% |

Floors | Value | Distance Error | |
---|---|---|---|

MGIF [10] | Proposed UFEE | ||

2F | Min | 1.00 m | 0.20 m |

Max | 12.00 m | 7.45 m | |

3F | Min | 1.00 m | 0.67 m |

Max | 12.00 m | 4.53 m | |

4F | Min | 1.00 m | 0.13 m |

Max | 11.40 m | 6.27 m |

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## Share and Cite

**MDPI and ACS Style**

Seong, J.-H.; Lee, S.-H.; Yoon, K.-K.; Seo, D.-H.
Ellipse Coefficient Map-Based Geomagnetic Fingerprint Considering Azimuth Angles. *Symmetry* **2019**, *11*, 708.
https://doi.org/10.3390/sym11050708

**AMA Style**

Seong J-H, Lee S-H, Yoon K-K, Seo D-H.
Ellipse Coefficient Map-Based Geomagnetic Fingerprint Considering Azimuth Angles. *Symmetry*. 2019; 11(5):708.
https://doi.org/10.3390/sym11050708

**Chicago/Turabian Style**

Seong, Ju-Hyeon, Seung-Hyun Lee, Kyoung-Kuk Yoon, and Dong-Hoan Seo.
2019. "Ellipse Coefficient Map-Based Geomagnetic Fingerprint Considering Azimuth Angles" *Symmetry* 11, no. 5: 708.
https://doi.org/10.3390/sym11050708