Open Access

SmartMIMO: An Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Next-Generation Wireless Local Area Networks

  • Bruno Bougard1, 2Email author,
  • Gregory Lenoir1,
  • Antoine Dejonghe1,
  • Liesbet Van der Perre1,
  • Francky Catthoor1, 2 and
  • Wim Dehaene2
EURASIP Journal on Wireless Communications and Networking20072007:098186

DOI: 10.1155/2007/98186

Received: 15 November 2006

Accepted: 8 October 2007

Published: 5 December 2007


Multiantenna systems and more particularly those operating on multiple input and multiple output (MIMO) channels are currently a must to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase. However, multiantenna techniques also come with an overhead in silicon implementation area and power consumption due, at least, to the duplication of part of the transmitter and receiver radio front-ends. Although the area overhead may be acceptable in view of the performance improvement, low power consumption must be preserved for integration in nomadic devices. In this case, it is the tradeoff between performance (e.g., the net throughput on top of the medium access control layer) and average power consumption that really matters. It has been shown that adaptive schemes were mandatory to avoid that multiantenna techniques hamper this system tradeoff. In this paper, we derive smartMIMO: an adaptive multiantenna approach which, next to simply adapting the modulation and code rate as traditionally considered, decides packet-per-packet, depending on the MIMO channel state, to use either space-division multiplexing (increasing spectrum efficiency), space-time coding (increasing robustness), or to stick to single-antenna transmission. Contrarily to many of such adaptive schemes, the focus is set on using multiantenna transmission to improve the link energy efficiency in real operation conditions. Based on a model calibrated on an existing reconfigurable multiantenna transceiver setup, the link energy efficiency with the proposed scheme is shown to be improved by up to 30% when compared to nonadaptive schemes. The average throughput is, on the other hand, improved by up to 50% when compared to single-antenna transmission.


Authors’ Affiliations

Department of Nomadic Embedded Systems, IMEC
K. U. Leuven, Department of Electrical Engineering, Katholieke Universiteit Leuven, ESAT


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© Bruno Bougard et al. 2007

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