A Non-cooperative Game Approach for RAN and Spectrum Sharing in Mobile Radio Networks

Mobile Network Operators (MNOs) are nowadays forced to continuously invest in their network infrastructure to keep up with the increasing bandwidth demand and traffic load coming from mobile users. In this context, MNOs have to face the strategic problem of whether to invest on their own or deploy shared networks. We address here the problem of Radio Access Network (RAN) and spectrum sharing in 4G mobile networks. Namely, we consider the case in which multiple MNOs are planning to deploy small cell Base Stations to improve their current network infrastructure; the deployment investment may be shared with other MNOs, thus giving rise to shared RANs. The RAN and spectrum sharing problem is formalized as a Generalized Nash Equilibrium Problem, where the strategy of each MNO in the game is twofold: selecting a coalition (whom to cooperate) and the fraction of the coalition cost to pay, with the goal of maximizing the individual return on investment. The proposed approach is leveraged to characterize the stable coalitions and their respective cost division policies for various network and economic conditions.