# Complexity Effective Sampling Frequency Offset Estimation Method for OFDM-Based HomePlug Green PHY Systems

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Signal Model

## 3. Conventional SFO Estimation Scheme

#### 3.1. Conventional Scheme A

#### 3.2. Conventional Scheme B

#### 3.3. Conventional Scheme C

## 4. Proposed SFO Estimation Scheme

#### 4.1. Estimation Algorithm

#### 4.2. MSE Analysis

#### 4.3. Complexity

## 5. Simulation Results and Discussions

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Mean square error (MSE) comparison between the proposed and conventional estimation schemes versus signal to noise ratio (SNR): (

**a**) High-speed robust orthogonal frequency division multiplexing (ROBO) mode (

**b**) Standard ROBO mode.

**Figure 2.**MSE comparison between the proposed and conventional estimation schemes versus sampling frequency offset (SFO): (

**a**) High-speed ROBO mode (

**b**) Standard ROBO mode.

**Figure 3.**Bit error rate (BER) comparison between the proposed and conventional estimation schemes versus SFO: (

**a**) High-speed ROBO mode (

**b**) Standard ROBO mode.

Mode | PHY Rate | # Repeat Copies |
---|---|---|

Mini ROBO | 3.8 Mbps | 5 |

Standard ROBO | 4.9 Mbps | 4 |

High-speed ROBO | 9.8 Mbps | 2 |

Parameter | Value |
---|---|

Sampling rate | ${f}_{s}=75$ MHz |

FFT size | $N=3072$ |

CP size | ${N}_{g}=417$ |

Number of subcarriers | ${N}_{b}=1155$ |

Number of non-masked subcarriers | ${N}_{c}=916$ |

Modulation | QPSK |

Index m | Standard ROBO | High-Speed ROBO | ||
---|---|---|---|---|

Subcarrier Distance ${\mathit{F}}_{\mathit{m}}$ | # of Subcarrier ${\mathit{N}}_{\mathit{m}}$ | Subcarrier Distance ${\mathit{F}}_{\mathit{m}}$ | # of Subcarrier ${\mathit{N}}_{\mathit{m}}$ | |

1 | 676 | 54 | 816 | 54 |

2 | 648 | 41 | 788 | 47 |

3 | 674 | 6 | 777 | 13 |

4 | 663 | 13 | 789 | 44 |

5 | 396 | 44 | 769 | 71 |

6 | 376 | 58 | 261 | 36 |

7 | 388 | 13 | 251 | 66 |

8 | 654 | 36 | 263 | 84 |

9 | 644 | 79 | 241 | 24 |

10 | 403 | 71 | 267 | 19 |

11 | 381 | 43 | - | - |

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## Share and Cite

**MDPI and ACS Style**

Jung, Y.-A.; You, Y.-H.
Complexity Effective Sampling Frequency Offset Estimation Method for OFDM-Based HomePlug Green PHY Systems. *Symmetry* **2018**, *10*, 544.
https://doi.org/10.3390/sym10110544

**AMA Style**

Jung Y-A, You Y-H.
Complexity Effective Sampling Frequency Offset Estimation Method for OFDM-Based HomePlug Green PHY Systems. *Symmetry*. 2018; 10(11):544.
https://doi.org/10.3390/sym10110544

**Chicago/Turabian Style**

Jung, Yong-An, and Young-Hwan You.
2018. "Complexity Effective Sampling Frequency Offset Estimation Method for OFDM-Based HomePlug Green PHY Systems" *Symmetry* 10, no. 11: 544.
https://doi.org/10.3390/sym10110544