다중 사용자 OFDM 시스템에서 효율적인 자원 활용을 위한 향상된 유전자 알고리즘 기반의 비트-부반송파 할당방법

Improved Genetic Algorithm Based Bit and Subcarrier Allocation Scheme for Efficient Resource Use in Multiuser OFDM Systems

  • 송정섭 (강원대학교 전기전자공학부) ;
  • 김성수 (강원대학교 산업공학과) ;
  • 장갑석 (한국전자통신연구원) ;
  • 김동회 (강원대학교 전기전자공학부)
  • 발행 : 2008.11.30

초록

다중 사용자 OFDM 시스템에서 제한된 자원을 효율적으로 사용하기 위해서는 부반송파와 비트의 할당은 중요한 역할을 한다. 하지만 부반송파와 비트의 할당문제는 비선형적 문제로 모든 경우의 수를 계산하여 최적의 값을 얻기에는 사실상 불가능하다. 본 논문에서는 비선형적 문제의 효율적인 자원 활용을 위해서 새로운 유전자 알고리즘을 사용하였다. 논문에서 제안된 알고리즘은 기존의 정형화된 유전자 알고리즘보다 다양한 조합을 참고하여 해를 찾게 된다. 따라서 수치적 시뮬레이션 결과들을 통해서 기존의 알고리즘들과 제안된 알고리즘을 비교해 볼 때, 제안한 알고리즘이 기존의 알고리즘들보다 뛰어난 성능을 보임을 확인하였다.

In multiuser OFDM systems, subcarrier and bit allocation plays an important role for the efficient resource use. However, in multiuser adaptive allocation as a non-linear problem, it is impractical to compute all to get the best solution because of the complexity. We set the goal of minimizing the transmit power while satisfying the BER and minimum bits required to transmit through the highest fitness combination of subcarriers and users. The proposed improved genetic algorithm employs the diversity of adaptive allocation more than existing genetic algorithm. Therefore, from the numerical simulation results, we find that the proposed heuristic algorithm has more performance than the existing algorithms.

키워드

참고문헌

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