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Joint Subcarrier and Power Allocation for a Downlink OFDMA Relay Network in Multi-Cell Environments

다중 셀 환경에서 하향 링크 OFDMA 중계 네트워크를 위한 부반송파 및 전력 할당 기법

  • Choi, Dong-Wook (School of Electrical Engineering, Seoul National University) ;
  • Lee, Jae-Hong (School of Electrical Engineering, Seoul National University)
  • 최동욱 (서울대학교 전기컴퓨터공학부, 뉴미디어통신공동연구소) ;
  • 이재홍 (서울대학교 전기컴퓨터공학부, 뉴미디어통신공동연구소)
  • Received : 2009.12.28
  • Accepted : 2010.03.03
  • Published : 2010.03.30

Abstract

In this paper, we propose a new resource allocation scheme for an OFDMA relay network with multicells. In the proposed scheme, by sharing the channel state information (CSI) between base stations, resources are allocated to users and relays to maximize the overall sum of the achievable rate under fairness constraints. In order to reduce the computational complexity, a resource allocation scheme is proposed by separating subcarrier allocation and power allocation into two parts. First of all, by considering inter-cell interference (ICI), a subcarrier is allocated to a user-relay pair, and power is allocated relays. Simulation results show that the proposed scheme achieves higher spectral efficiency per subcarrier than the static scheme and reduces the outage probability compared to the static and greedy schemes.

본 논문에서는 다중 셀 환경의 OFDMA 중계 네트워크를 위한 새로운 자원 할당 기법에 대해서 제안한다. 제안된 기법에서는 기지국 간의 채널정보를 공유하여 공평성 제한을 갖으면서 전체통신용량이 최대가 되도록 수신단말기와 중계단말기에 자원을 할당한다. 계산량을 줄이기 위해 자원할당 과정은 두 부분으로 나뉘어 진행된다. 먼저 셀간 간섭을 고려하여 수신단말기와 중계단말기에 부반송파를 할당하고, 이후 중계단말기의 부반송파에 전력을 할당한다. 모의실험 결과에서 제안된 기법이 부반송파 당 더 높은 주파수 효율을 얻는 다는 것을 확인하였다. 또한 제안된 기법이 static과 greedy 기법에 비하여 오수신 확률(outage probability)이 낮음을 확인하였다.

Keywords

References

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