High SNR Analysis of User-Multiplexing Technique Provisioning Delay QoS in OFDMA Systems

OFDMA 시스템에서 지연 QoS를 지원하는 2-D 사용자 다중화 기법에 대한 높은 SNR영역에서의 성능 분석

  • Ahn, Seong-Woo (Dept. of Electrical and Electronic Engin., Yonsei University) ;
  • Hong, Dae-Sik (Dept. of Electrical and Electronic Engin., Yonsei University)
  • 안성우 (연세대학교 전기전자공학부) ;
  • 홍대식 (연세대학교 전기전자공학부)
  • Received : 2011.01.07
  • Accepted : 2011.04.14
  • Published : 2011.04.25

Abstract

In this paper, we study the throughput-delay tradeoff of OFDMA systems in context of 2-dimensional resource allocation, and analyze the effect of frequency diversity and user-multiplexing in time domain that has on delay QoS performance. Based on the analysis results, we investigate the impacts of delay QoS on spectral efficiency. In high SNR regime, the optimal DoM (degree of multiplexing) maximizing the spectral efficiency is identified. The results of the high SNR analysis can give us an intuition on an efficient resource allocation policy. Finally, through the simulation results, we verify that our approach with its optimal DoM yields substantial capacity gain.

본 논문은 OFDMA 시스템에서 지연 QoS와 시스템 용량 간의 트레이드오프에 대해 2차원 자원할당 관점에서 살펴보고, 주파수 다이버시티와 시간축 사용자 다중화가 지연 QoS 성능에 미치는 영향을 분석하였다. 이를 바탕으로 지연 QoS가 시스템의 주파수 효율 (spectral efficiency)에 영향을 미치는 영향을 살펴보았다. 특히, 높은 SNR 영역에서 시간축 다중화도 (degree of multiplexing)에 따른 주파수 효율의 변화를 분석하여 효율적인 다중화 기법에 대한 방향을 제시하였다. 마지막으로 모의실험을 통하여 분석 결과를 검증하였으며, 최적의 다중화도를 이용할 때 상당한 성능이득을 얻을 수 있음을 확인하였다.

Keywords

References

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