Energy-efficient channel estimation in MIMO systems

Abstract

The emergence of MIMO communications systems as practicalhigh-data-rate wireless communications systems hascreated several technical challenges to be met. On the one hand,there is potential for enhancing system performance in terms ofcapacity and diversity. On the other hand, the presence of multiple transceivers at both ends hascreated additional cost in terms of hardware and energyconsumption. For coherent detection as well as to do optimizationsuch as water filling and beamforming, it is essential that theMIMO channel is known. However, due to the presence of multipletransceivers at both the transmitter and receiver, the channelestimation problem is more complicated and costly compared to aSISO system. Several solutions have been proposed to minimize thecomputational cost, and hence the energy spent in channelestimation of MIMO systems. We present a novel method ofminimizing the overall energy consumption. Unlike existingmethods, we consider the energy spent during the channelestimation phase which includes transmission of training symbols,storage of those symbols at the receiver, and also channelestimation at the receiver. We develop a model that is independentof the hardware or software used for channel estimation, and use adivide-and-conquer strategy to minimize the overall energyconsumption.