# Dynamic Clustering and Coordinated User Scheduling for Cooperative Interference Cancellation on Ultra-High Density Distributed Antenna Systems

## Abstract

**:**

## 1. Introduction

## 2. System Model and Schemes

**H**is then expressed as,

#### 2.1. Inter-Cluster Interference Cancellation

#### 2.2. Computation Complexity

## 3. Proposed Scheme: Dynamic Clustering and Coordinated User Scheduling

## 4. Computer Simulation

#### 4.1. Simulation Parameters

Algorithm 1 Simulation process. | |

Initialization: | |

1: | Set the scheduled UEs per cluster: ${\varphi}_{i}=\varnothing $, $i=1,\dots ,M$ |

2: | Set the UEs per cell: $X\left(j\right)\in \{1,\dots ,\tilde{K}\}$ |

3: | Set the cells (RUs): $Y\in \{1,\dots ,j,\dots ,L\}$ |

4: | Set the clusters at the $\beta $th clustering state: ${Z}_{i}\in \{\{{z}_{1}^{\beta}\},\dots ,\{{z}_{M}^{\beta}\}\}$, $\beta =0,1,2$ |

Procedure: | |

5: | $n\leftarrow 0$ |

6: | while$|X(j)|>0$do |

7: | Determine cluster sets: $\beta \leftarrow n\phantom{\rule{0.277778em}{0ex}}mod\phantom{\rule{0.277778em}{0ex}}3$ |

8: | for $i=1$ to M do |

9: | ${\varphi}_{i}\leftarrow Coordinated\_Scheduling({z}_{i}^{\beta})$ |

10: | $X({z}_{i}^{\beta})\leftarrow X({z}_{i}^{\beta})\backslash {\varphi}_{i}$ |

11: | end for |

12: | Construct channel matrix: $\mathbf{H}=\{{\mathbf{H}}_{i,i}\}$ |

13: | ${\mathbf{W}}_{i}\leftarrow Gram\_Schmidt({\mathbf{H}}_{i,i})$ |

14: | Calculate residual interference term in Equation (18) |

15: | Calculate spectral efficiency in Equation (17) |

16: | $n\leftarrow n+1$ |

17: | end while |

18: | function$Coordinated\_Scheduling$(${z}_{i}^{\beta}$) |

19: | Find UEs $x\in X({z}_{i}^{\beta})$ locating in intra-cluster region |

20: | return x |

21: | end function |

#### 4.2. Simulation Results: Clustering and Scheduling Effect

- Case 1: All three UEs locate at cluster-edge region.
- Case 2: Two UEs locate at cluster edge and 1 UE at cluster center regions.
- Case 3: All three UEs locate at cluster-center region.

#### 4.3. Simulation Results: Dynamic Clustering and Inter-Cluster Interference Cancellation

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## Abbreviations

UHD-DAS | Ultra-High Density Distributed Antenna System |

MIMO | Multiple-Input Multiple-Output |

MU-MIMO | Multiuser MIMO |

Wi-Fi | Wireless Fidelity |

WiMAX | Worldwide Interoperability for Microwave Access |

LTE | Long Term Evolution |

BS | Base Station |

UE | User Equipment |

CoMP | Coordinated MultiPoint |

CU | Central Unit |

RU | Radio Unit |

ICI | Inter-Cell Interference |

ICLI | Inter-Cluster Interference |

CSI | Channel State Information |

FFR | Fractional Frequency Reuse |

AWGN | Additive White Gaussian Noise |

SNR | Signal-to-Noise power Ratio |

SINR | Signal-to-Interference and Noise power Ratio |

CDF | Cumulative Distribution Function |

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**Figure 5.**Coordinated UE scheduling strategies: (

**a**) Case 1, all UEs locate in cluster-edge region; (

**b**) Case 2, two UEs locate in cluster-edge and 1 UE is in center region; and (

**c**) Case 3, all UEs locate in cluster-center region.

Parameters | Values |
---|---|

Cell deployment | Hexagonal |

Number of UE | 50 per cell |

Cell edge SNR | 20 dB |

Cluster Size C | 3 |

Reuse Factor | 1 |

Inter-cluster interference cancellation order $\alpha $ | 1, 3 |

MU-MIMO transmission weight | Gram–Schmidt orthogonalization [20] |

Carrier frequency | 2 GHz |

Propagation model | ITU-R M.1225 Pedestrian B [23] 40.1log${}_{10}$ (d [m])+39 dB |

Fading model | i.i.d Rayleigh |

RU/UE antenna | Single, Omni directional |

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**MDPI and ACS Style**

Maruta, K.
Dynamic Clustering and Coordinated User Scheduling for Cooperative Interference Cancellation on Ultra-High Density Distributed Antenna Systems. *Entropy* **2018**, *20*, 616.
https://doi.org/10.3390/e20080616

**AMA Style**

Maruta K.
Dynamic Clustering and Coordinated User Scheduling for Cooperative Interference Cancellation on Ultra-High Density Distributed Antenna Systems. *Entropy*. 2018; 20(8):616.
https://doi.org/10.3390/e20080616

**Chicago/Turabian Style**

Maruta, Kazuki.
2018. "Dynamic Clustering and Coordinated User Scheduling for Cooperative Interference Cancellation on Ultra-High Density Distributed Antenna Systems" *Entropy* 20, no. 8: 616.
https://doi.org/10.3390/e20080616