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  • Research Article
  • Open Access

Spectrally Efficient Communication over Time-Varying Frequency-Selective Mobile Channels: Variable-Size Burst Construction and Adaptive Modulation

EURASIP Journal on Advances in Signal Processing20062006:035352

  • Received: 1 June 2005
  • Accepted: 15 March 2006
  • Published:


Methods for providing good spectral efficiency, without disadvantaging the delivered quality of service (QoS), in time-varying fading channels are presented. The key idea is to allocate system resources according to the encountered channel. Two approaches are examined: variable-size burst construction, and adaptive modulation. The first approach adapts the burst size according to the channel rate of change. In doing so, the available training symbols are efficiently utilized. The second adaptation approach tracks the operating channel quality, so that the most efficient modulation mode can be invoked while guaranteeing a target QoS. It is shown that these two methods can be effectively combined in a common framework for improving system efficiency, while guaranteeing good QoS. The proposed framework is especially applicable to multistate channels, in which at least one state can be considered sufficiently slowly varying. For such environments, the obtained simulation results demonstrate improved system performance and spectral efficiency.


  • Fading Channel
  • Spectral Efficiency
  • Modulation Mode
  • Channel Quality
  • Adaptive Modulation

Authors’ Affiliations

The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, ON, Canada, M5S 3G4


  1. Rappaport TS: Wireless Communications: Principles and Practice. Prentice Hall, Englewood Cliffs, NJ, USA; 1996.MATHGoogle Scholar
  2. Steele R, Hanzo L: Mobile Radio Communications: Second and Third Generation Cellular and WATM Systems. John Wiley & Sons, New York, NY, USA; 1999.View ArticleGoogle Scholar
  3. Hanzo L, Wong C, Yee M: Adaptive Wireless Transceivers: Turbo- Coded, Turbo-Equalized and Space-Time Coded TDMA, CDMA, and OFDM Systems. John Wiley & Sons, New York, NY, USA; 2002.View ArticleGoogle Scholar
  4. Bui FM, Hatzinakos D: A receiver-based variable-size-burst equalization strategy for spectrally efficient wireless communications. IEEE Transactions on Signal Processing 2005, 53(11):4304–4314.MathSciNetView ArticleGoogle Scholar
  5. Bui FM, Hatzinakos D: Adaptive modulation using variable-size burst for spectrally efficient interference suppression in wireless communications. Proceedings of IEEE Global Telecommunications Conference (GLOBECOM '04), November–December 2004, Dallas, Tex, USA 2: 898–902.View ArticleGoogle Scholar
  6. Bui FM, Hatzinakos D: Identification and tracking of rapidly time-varying mobile channels for improved equalization: a basis-expansion model approach. to appear in The 5th International Symposium on Communication Systems, Network and Digital Signal Processing (CSNDSP '06), Patras, GreeceGoogle Scholar
  7. Giannakis GB, Tepedelenlioglu C: Basis expansion models and diversity techniques for blind identification and equalization of time-varying channels. Proceedings of the IEEE 1998, 86(10):1969–1986. 10.1109/5.720248View ArticleGoogle Scholar
  8. Barhumi I, Leus G, Moonen M: Time-varying FIR equalization for doubly selective channels. IEEE Transactions on Wireless Communications 2005, 4(1):202–214.View ArticleGoogle Scholar
  9. Patzold M: Mobile Fading Channels. 1st edition. John Wiley & Sons, New York, NY, USA; 2002.View ArticleGoogle Scholar
  10. Dong M, Tong L: Optimal design and placement of pilot symbols for channel estimation. IEEE Transactions on Signal Processing 2002, 50(12):3055–3069. 10.1109/TSP.2002.805504View ArticleGoogle Scholar
  11. Haykin S: Adaptive Filter Theory. 3rd edition. Prentice Hall, Englewood Cliffs, NJ, USA; 1996.MATHGoogle Scholar
  12. Floudas CA: Nonlinear and Mixed-Integer Optimization: Fundamentals and Applications. Oxford University Press, New York, NY, USA; 1995.MATHGoogle Scholar
  13. Catreux S, Erceg V, Gesbert D, Heath RW: Adaptive modulation and MIMO coding for broadband wireless data networks. IEEE Communications Magazine 2002, 40(6):108–115. 10.1109/MCOM.2002.1007416View ArticleGoogle Scholar
  14. Proakis JG: Digital Communications. 4th edition. McGraw Hill, New York, NY, USA; 2001.MATHGoogle Scholar
  15. Balaban P, Salz J: Optimum diversity combining and equalization in digital data transmission with applications to cellular mobile radio. I: theoretical considerations. IEEE Transactions on Communications 1992, 40(5):885–894. 10.1109/26.141454View ArticleGoogle Scholar
  16. Wong CH, Hanzo L: Upper-bound performance of a wide-band adaptive modem. IEEE Transactions on Communications 2000, 48(3):367–369. 10.1109/26.837037View ArticleGoogle Scholar


© Bui and Hatzinakos 2006