The Journal of Korean Institute of Communications and Information Sciences (한국통신학회논문지)

The Korean Institute of Commucations and Information Sciences (한국통신학회)
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Efficient Power and Rate Adaptation Strategy for Improved Spectral Efficiency in Multi-Carrier DS-CDMA Communications

다중 반송파 부호분할 다중접속 통신에서의 주파수 효율 향상을 위한 효율적인 전력 및 전송률 적응화 기법

  • 이예훈 (서울과학기술대학교 전자IT미디어공학과) ;
  • 김동호 (서울과학기술대학교 전자IT미디어공학과)
  • Received : 2013.07.31
  • Accepted : 2013.08.12
  • Published : 2013.08.30
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Abstract

We propose an efficient frequency-time domain resource allocation scheme in multi-carrier (MC) direct-sequence code-division multiple-access (DS/CDMA) communications. We consider, as a power allocation strategy in the frequency domain, transmitting each user's DS waveforms over the user's sub-band with the largest channel gain. We then consider rate adaptation in the time domain, where the data rate is adapted such that a desired transmission quality is maintained. We analyze the achievable average data rate of the proposed scheme with fixed average transmission power, and compare the performance to single carrier DS/CDMA systems with power and rate adaptations.

다중 반송파를 사용하는 직접 대역확산 부호분할 다중접속 통신시스템에서 주파수 효율 향상을 위한 전송 전력 및 전송률 적응화 시스템을 제안하고 그 성능을 분석하였다. 본 논문에서는 수신단에서 이상적인 채널상태 정보를 알고 있다는 가정 하에, 주파수 영역에서는 각 사용자의 부채널 중에서 가장 채널상태가 좋은 한 대역을 선택하여 전력을 할당하고 시간 영역에서는 목표 수신 품질을 만족하도록 전송률을 결합 조정하는 것을 제안하였다. 수학적 분석을 통하여 평균 전송 전력이 고정되어 있을 때 제안한 방식의 평균 데이터 전송률을 구하고 전력 혹은 전송률 적응화가 적용된 단일 반송파 부호분할 다중접속 통신시스템과 그 성능을 비교하였다.

Keywords

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