Capacity Optimization of a 802.16e OFDMA/TDD Cellular System using the Joint Allocation Algorithm of Sub-channel and Transmit Power Part I : Sub-channel Allocation Algorithm for Throughput Maximization in the Downlink insuring Fairness and Power Allocation Algorithm for efficient use of Extra Transmit Power efficiently

802.16e OFDMA/TDD 셀룰러 시스템의 성능 최적화를 위한 부채널과 전송전력 결합 할당 알고리즘 Part I : 하향링크에서 공평성이 보장되는 수율 최대화 부채널 할당 알고리즘 및 잉여 전송전력의 효율적인 사용을 위한 전력할당 알고리즘

  • 고상준 (인하대학교 정보통신대학원 이동통신연구실) ;
  • 장경희 (인하대학교 정보통신대학원 이동통신연구실) ;
  • 김재형 (포스데이타 WiMAX/WiBro 시스템 개발부)
  • Published : 2007.03.31

Abstract

This paper solves the problem of finding a suitable sub-channel and power joint allocation method for multiple users in 802.16e OFDMA/TDD cellular systems. The joint allocation is thatfirstly the sub-channel is allocated to the users and then suitable power is allocated. We propose a FASA (Fairness insured Aggressive Sub-channel Allocation) algorithm which is a dynamic channel allocation algorithm considering all users' channel state information conditionally to maximize fairness and throughput. The improved CHC algorithm, which is dynamic power allocation algorithm, is also proposed in this paper The Improved CHC algorithm collects the extra of the downlink transmit power and then re-allocates it to other users. Simulation results show that the proposed improved CHC algorithm additionally increases the fairness and sector throughput.

본 논문에서는 802.16e OFDMA/TDD 시스템의 하향링크에서 제안된 FASA (Fairness insured Aggressive Sub-channel Allocation) 알고리즘을 적용하여 사용자에게 적절한 부채널을 할당한 후, 제안된 Improved CHC 알고리즘을 통해 적절한 전송전력을 할당하는 결합할당 알고리즘을 제안한다. FASA 알고리즘은 선택된 사용자에게 최대의 채널 이득을 보장해줄 수 있는 복수개의 부채널이 존재할 경우, 그 중 주변 사용자들에게 가장 적은 채널이득을 보장해주는 부채널을 선택된 사용자에게 할당함으로써 시스템의 Throughput을 최대화 시키는 알고리즘이다. 또한 본 논문에서 제안된 Improved CHC 알고리즘은 사용자에게 할당되는 하향링크 전송 전력 중, 잉여전력을 수거하고 재할당함으로써 시스템의 전송전력할당의 효율성을 최대화 시키는 알고리즘이다. Improved CHC 알고리즘을 통해 추가적인 Throughput 및 공평성의 향상을 얻을 수 있다.

Keywords

References

  1. Cheong Yui Wong, Cheng, R.S., Lataief, K.B., and Murch, R.D., 'Multiuser OFDM with adaptive subcarrier, bit, and power allocation,' IEEE J. Selected Areas in Commun., pp. 1747-1758, Oct. 1999
  2. Kivanc, D., G. Li, and Hui Liu, 'Computationally efficient bandwidth allocation and power control for OFDMA,' IEEE Transaction on Wireless Commun., pp. 1150-1158, Nov. 2003
  3. J. Heo, I.S. Cha, and K.H. Chang, 'A novel transmit power allocation algorithm combined with dynamic channel allocation in reuse partitioning-based OFDMA/FDD system,' in Proc. IEEE ICC, June 2006, WC52-4
  4. J. Heo, S.H. Park , and K.H. Chang, 'An effective downlink resource allocation for supporting heterogen eous traffic data in an OFDM/SDMAbased cellular system,' in Proc.GLOBECOM, Nov. 2006
  5. J. Heo and K.H. Chang, 'Transmit and receive beam forming for OFDMA/TDD system,' International Symposium on Antenna and Propagation, Aug. 2005, pp.27-30
  6. Aniba G. and Aissa S, 'Adaptive proportional fairness for packet scheduling in HSDPA,' in proc. IEEE GLOBECOM, Nov. 2004, pp. 4033-4037
  7. Wengerter, C., Ohlhorst, J., and Elbwart, A.G.E., 'Fairness and throughput analysis for generalized proportional fair frequency scheduling in OFDMA,' in proc. IEEE VTC Spring, May 2005, pp.1903-1907
  8. Jiho Jang and Kwang Bok Lee, 'Transmit power adaptation for multiuser OFDM systems,' IEEE J. Selected Areas in Commun., pp. 171-178, Feb. 2003
  9. S.J. Ko, J. Heo, and K.H. Chang, 'Aggressive sub-channel allocation algorithm for intelligent transmission in multi-user OFDMA system,' LNAI, KES (International Conference on Knowledge-Based & Intelligent Information & Engineering Systems), Oct. 2006
  10. S.J. Ko, J. Heo, and K.H. Chang, 'Aggressive sub-channel allocation algorithm for efficient dynamic channel allocation in multi-user OFDMA system,' in Proc. PIMRC, Mar. 2006
  11. 고상준, 허 주, 장경희, '다중 사용자 OFDMA 시스템에서의 사용자간 전송효율 최적화를 위한 aggressive sub-channel allocation 알고리즘,' 한국통신학회 논문지, pp. 617-626, 2006. 06
  12. IEEE P802.16e / D11-2004 IEEE Standards for local and metropolitan area networks part 16 : Air interface for fixed broadband wireless access systems
  13. 3GPP R1-030042, Update of OFDM SI Simulation Methodology, Jan. 2003
  14. Recommendation ITU-R M.1225, Guidelines for Evaluation of Radio Transmission Technologies for IMT-2000, 1997
  15. CDG Evolution Study Report, Revision 4.00, Dec. 1999