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

Multiple-antenna techniques (MIMO) have been proposed to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase. But these multiple-antenna techniques come with an overhead in power consumption due to the duplication of part of the transmitter and receiver front-ends. From a system perspective, one has to focus on performance versus power consumption tradeoff. In this paper, we derive SmartMIMO: an adaptive energy-aware link adaptation approach which, next to the modulation and code rate, decides on using either space-division multiplexing (increasing spectrum efficiency) or space-time coding (increasing robustness) to transmit a given packet on a given MIMO channel. Energy-efficiency is shown to be improved by up to 30% when compared to non-adaptive techniques while the average rate is improved by up to 50% when compared to single-antenna transmission