A stable marriage framework for distributed virtual MIMO coalition formation

In this paper, a distributed algorithm for energy efficient virtual Multiple-input Multiple-output (MIMO) coalition formation is proposed. We model cooperation as a game theoretic approach derived from the concept of stable marriage with incomplete lists (SMI). Thus, single antenna devices such as mobile and relay stations are allowed to cooperate in order to improve the user´s and system´s energy efficiency. Our approach is focused on optimizing the circuit consumed power of the single antenna devices rather than on the transmitted power, thus the total device power consumption including the effect of the power amplifiers is taken into account. Furthermore, we show analytically and by simulation that under certain conditions cooperation does not improve the energy efficiency metric of network users, thus single antenna devices prefer to transmit independently in order to maintain the user´s performance in the network. Additionally, our distributed approach reduces the communication overhead by 76% when compared with a centralized global optimum scheme, which is coordinated from the base station.