Energy-efficient power allocation with dual-utility in two-tier OFDMA femtocell networks

Abstract

This paper investigates the downlink power allocation problem to mitigate the cross- and co-tier interference in the spectrum-sharing two-tier OFDMA femtocell network, which are comprised of macrocells underlaid with femtocells. The problem is formulated as a non-cooperative game with dual-utility. To achieve green radio access, the objective of the utility for each macro BS is to maximize its energy efficiency under power constraints in each sub-channel, and both circuit and transmit powers have been considered, while the objective of the utility for each femto BS is to maximize its own SINR for customers' interests. Then, the existence, characteristic and uniqueness of the equilibrium for the proposed game are studied. With practical LTE parameters and three-dimensional femtocell network model, simulation results show that the proposed scheme can improve energy efficiency of macrocell networks and mitigate the cross- and co-tier interference significantly while guaranteeing the minimum QoS requirement of femtocell users.