Price-based power control with statistical delay QoS guarantee in two-tier femtocell networks

Macrocells may suffer serious interference induced by the deployment of co-channel femtocells. To mitigate the cross-interference, we design a novel price-based power control method, with each femtocell user´s delay quality-of-service (QoS) provisioning, in uplink OFDMA two-tier femtocell networks. Assuming that the macrocell base station (MBS) protects itself by pricing the interference from femtocell users (FU), a Stackelberg game is formulated with a goal to reach the joint utility maximization of the macrocell and the femtocells subject to a maximum tolerable interference power at the MBS. The Nash Equilibrium (NE) of its non-cooperative subgame is found with optimization theory firstly, and then a particle swarm optimization (PSO) aided power allocation (PSO-PA) algorithm is proposed to achieve the final Stackelberg Equilibrium (SE). Simulation results show that our proposed power allocation algorithm can converge quite fast and bring much higher effective capacity (EC) at FU side.