Open Access

Capacity Planning for Group-Mobility Users in OFDMA Wireless Networks

EURASIP Journal on Wireless Communications and Networking20062006:075820

https://doi.org/10.1155/WCN/2006/75820

Received: 11 October 2005

Accepted: 26 May 2006

Published: 28 June 2006

Abstract

Because of the random nature of user mobility, the channel gain of each user in a cellular network changes over time causing the signal-to-interference ratio (SNR) of the user to fluctuate continuously. Ongoing connections may experience outage events during periods of low SNR. As the outage ratio depends on the SNR statistics and the number of connections admitted in the system, admission capacity planning needs to take into account the SNR fluctuations. In this paper, we propose new methods for admission capacity planning in orthogonal frequency-division multiple-access (OFMDA) cellular networks which consider the randomness of the channel gain in formulating the outage ratio and the excess capacity ratio. Admission capacity planning is solved by three optimization problems that maximize the reduction of the outage ratio, the excess capacity ratio, and the convex combination of them. The simplicity of the problem formulations facilitates their solutions in real time. The proposed planning method provides an attractive means for dimensioning OFDMA cellular networks in which a large fraction of users experience group-mobility.

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Authors’ Affiliations

(1)
Department of Electrical and Computer Engineering (ECE), University of British Columbia (UBC)

References

  1. Wong CY, Cheng RS, Letaief KB, Murch RD: Multiuser OFDM with adaptive subcarrier, bit, and power allocation. IEEE Journal on Selected Areas in Communications 1999,17(10):1747-1758. 10.1109/49.793310View ArticleGoogle Scholar
  2. Kivanc D, Li G, Liu H: Computationally efficient bandwidth allocation and power control for OFDMA. IEEE Transactions on Wireless Communications 2003,2(6):1150-1158. 10.1109/TWC.2003.819016View ArticleGoogle Scholar
  3. Ergen M, Coleri S, Varaiya P: Qos aware adaptive resource allocation techniques for fair scheduling in OFDMA based broadband wireless access systems. IEEE Transactions on Broadcasting 2003,49(4):362-370. 10.1109/TBC.2003.819051View ArticleGoogle Scholar
  4. Mohanram C, Bhashyam S: A sub-optimal joint subcarrier and power allocation algorithm for multiuser OFDM. IEEE Communications Letters 2005,9(8):685-687. 10.1109/LCOMM.2005.1496582View ArticleGoogle Scholar
  5. Zhang YJ, Letaief KB: Multiuser adaptive subcarrier-and-bit allocation with adaptive cell selection for OFDM systems. IEEE Transactions on Wireless Communications 2004,3(5):1566-1575. 10.1109/TWC.2004.833501View ArticleGoogle Scholar
  6. Han Z, Ji Z, Ray Liu KJ: Fair multiuser channel allocation for OFDMA networks using Nash bargaining solutions and coalitions. IEEE Transactions on Communications 2005,53(8):1366-1376. 10.1109/TCOMM.2005.852826View ArticleGoogle Scholar
  7. Yao Y, Giannakis GB: Rate-maximizing power allocation in OFDM based on partial channel knowledge. IEEE Transactions on Wireless Communications 2005,4(3):1073-1083.View ArticleGoogle Scholar
  8. Niyato D, Hossain E: Connection admission control algorithms for OFDM wireless networks. Proceedings of IEEE Global Telecommunications Conference (GLOBECOM '05), November-December 2005, St. Louis, Mo, USA 2455-2459.Google Scholar
  9. Wang L-C, Huang S-Y, Tseng Y-C: Interference analysis and resource allocation for TDD-CDMA systems to support asymmetric services by using directional antennas. IEEE Transactions on Vehicular Technology 2005,54(3):1056-1069. 10.1109/TVT.2005.844660View ArticleGoogle Scholar
  10. Casoni M, Immovilli G, Merani ML: Admission control in T/CDMA systems supporting voice and data applications. IEEE Transactions on Wireless Communications 2002,1(3):540-548. 10.1109/TWC.2002.800552View ArticleGoogle Scholar
  11. Ross S: Stochastic Processes. 2nd edition. John Wiley & Sons, New York, NY, USA; 1996.MATHGoogle Scholar
  12. Lee K-D: Variable-target admission control for nonstationary handover traffic in LEO satellite networks. IEEE Transactions on Vehicular Technology 2005,54(1):127-135. 10.1109/TVT.2004.838893View ArticleGoogle Scholar

Copyright

© K.-D. Lee and V. C. M. Leung. 2006

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.