Dormancy Mechanism Based Power Allocation in Heterogeneous Networks: A Stackelberg Game Approach

In two-tier heterogeneous networks (HetNets) that consist of a central macrocell underlaid with spectrum-sharing dense smallcells, one primary concern is the cross-tier interference limits the network capacity. On the other hand, dormancy mechanism of smallcells is an emerging technique that can improve energy efficiency and mitigate interference. Therefore in this paper, we propose a power optimization oriented Stackelberg game considering dormancy mechanism for the downlink of two-tier HetNets. First, the smallcell dormancy mechanism is introduced to control the smallcells' operation. Then the Stackelberg game framework is developed. A sub game based on a potential theory is further formulated to optimize the transmit power of the active smallcells, which is demonstrated to converge to a pure and unique Nash equilibrium. In this sub game, the interference pricing mechanism is employed to price the cross-tier interference caused by smallcells and hence restricts the utility function of smallcells. Simulation results show that the proposed Stackelberg game based on dormancy mechanism with interference pricing can improve the smallcell network throughput and meanwhile reduce the average transmit power of smallcells.