Journal of the Korea Institute of Information and Communication Engineering (한국정보통신학회논문지)

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
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Threshold based User-centric Clustering for Cell-free MIMO Network

셀프리 다중안테나 네트워크를 위한 임계값 기반 사용자 중심 클러스터링

  • Ryu, Jong Yeol (Department of Information and Communication Engineering, Institute of Marine Industry, Gyeongsang National University) ;
  • Lee, Woongsup (Department of Information and Communication Engineering, Institute of Marine Industry, Gyeongsang National University) ;
  • Ban, Tae-Won (Department of Information and Communication Engineering, Institute of Marine Industry, Gyeongsang National University)
  • Received : 2021.11.08
  • Accepted : 2021.11.16
  • Published : 2022.01.31
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Abstract

In this paper, we consider a user centric clustering in order to guarantee the performance of the users in cell free multiple-input multiple-output (MIMO) network. In the user centric clustering scheme, by using large scale fading coefficients of the connected access points (APs), each user decides own cluster with the APs having the higher the large scale fading coefficients than threshold value compared to the highest large scale fading coefficient. In the determined user centric clusters, the APs design the beamformers and power allocations in the distributed manner and the APs cooperatively transmit data to users by using beamformers and power allocations. In the simulation results, we verify the performance of user centric clustering in terms of the spectral efficiency and we also find the optimal threshold value in the given configuration.

본 논문에서는 셀프리 다중안테나 환경에서 네트워크 전체 사용자의 성능을 보장하기 위한 사용자 중심의 클러스터링 기법을 고려한다. 사용자 중심 클러스터링 기법에서 각 사용자는 자신과 연결된 AP(Access Point)들 사이의 대규모 페이딩(large-scale fading) 채널 정보를 이용해 페이딩 계수가 가장 큰 AP와 페이딩 계수의 상대적 크기가 임계값 이상의 값을 갖는 AP들로 클러스터를 구성한다. 사용자 중심으로 구성된 클러스터를 바탕으로 AP들은 분산적인 기법으로 빔형성과 전력할당을 설계하고 이를 이용해 사용자들의 데이터를 협력 전송한다. 시뮬레이션을 통해 주파수 효율 관점에서 사용자 중심 클러스터링의 성능을 검증하고 주어진 환경에서 최적의 성능을 나타내는 임계값을 찾는다.

Keywords

Acknowledgement

This work was supported by Institute of Information & communications Technology Planning & Evaluation (IITP) grant funded by the Korea government(MSIT) (No.2018-0-00218, Speciality Laboratory for Wireless Backhaul Communications based on Very High Frequency)

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