Impact of Mobility on MIMO Green Wireless Systems

TL;DR

This paper analyzes how mobility affects power consumption in MIMO wireless systems, revealing the need for increased power to maintain rates and identifying optimal antenna configurations for energy efficiency.

Contribution

It quantifies the power increase needed for mobility in MIMO links and identifies the optimal number of antennas for energy-efficient communication.

Findings

Power consumption increases with mobility and coherence time.

Optimal number of antennas minimizes power for given conditions.

Lower bounds on power for green MIMO networks are established.

Abstract

This paper studies the impact of mobility on the power consumption of wireless networks. With increasing mobility, we show that the network should dedicate a non negligible fraction of the useful rate to estimate the different degrees of freedom. In order to keep the rate constant, we quantify the increase of power required for several cases of interest. In the case of a point to point MIMO link, we calculate the minimum transmit power required for a target rate and outage probability as a function of the coherence time and the number of antennas. Interestingly, the results show that there is an optimal number of antennas to be used for a given coherence time and power consumption. This provides a lower bound limit on the minimum power required for maintaining a green network.