Efficient power control in heterogeneous Femto-Macro cell networks

In this paper, we analyze the non-cooperative power control algorithm based on game theory in the two-tier femtocell networks, and find that the outcome of the game in a Nash equilibrium (NE) is inefficient. That is to say, there are still many users that can not achieve the target Signal-to-Interference-Plus-Noise Ratio (SINR) at the NE point, especially femtocell user equipments (FUE). Therefore, we propose a novel power control scheme in heterogeneous Femto-Macro cell networks, which can guarantee the target SINR of the macrocell user (MUEs), and make as many as possible FUEs to achieve their target SINRs. The proposed power control algorithm introduces the user selection and channel re-allocation in the conventional non-cooperative power control game. In addition, to further optimize the proposed scheme, we propose a novel FUE-SINR based MUE link quality protection algorithm. The propose scheme is able to improve the efficiency of Nash equilibrium, i.e., ensure more users to attain the target SINRs. Numerical simulations verify the conclusions.