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

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
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Power Re-Allocation for Low-Performance User in Cell-free MIMO Network

셀프리 다중안테나 네트워크에서 하위 성능 사용자를 위한 전력 재할당 기법

  • Ryu, Jong Yeol (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) ;
  • Lee, Woongsup (Department of Information and Communication Engineering, Institute of Marine Industry, Gyeongsang National University)
  • Received : 2022.08.22
  • Accepted : 2022.09.06
  • Published : 2022.09.30
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Abstract

In this paper, we consider a power re-allocation technique in order to enhance the frequency efficiency of the low performance user in a cell-free multiple input multiple output (MIMO) network. The AP first allocates transmit power to the user to be proportional to the large-scale fading coefficients of the connected users. Then, the AP reduces the power of the users who were allocated power greater than the threshold ratio of total allocated power to be equal to the threshold ratio of the allocated power. Finally, the AP re-allocates the reduced power from the strong channel user to the user who has the worst channel condition, and thus, the frequency efficiency of the low performance user can be enhanced. In the simulation results, we verify the performance of the power re-allocation technique in terms of the spectral efficiency of the low performance user.

본 논문에서는 셀프리 다중안테나 네트워크에서 하위 성능 사용자의 주파수 효율을 증대시키기 위한 전력 재할당 기법을 고려한다. AP(Access Point)는 사용자의 대규모 페이딩(large-scale fading) 채널 정보를 이용해 채널 세기에 비례하여 전력을 할당하여 전체 네트워크의 전력효율을 극대화한다. 다음으로 AP는 하위 성능 사용자의 주파수 효율을 증가시키기 위해 할당전력 중 임계비율 이상의 전력을 할당받은 사용자의 전력을 임계비율과 같아지도록 줄이고, 회수한 전력을 채널이 가장 나쁜 사용자에게 추가로 할당한다. 시뮬레이션을 통해 전력 재할당 기법을 통해 증가시킬 수 있는 하위 성능 사용자의 주파수 효율을 정량적으로 검증한다.

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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