Rate Maximization for Hybrid Access Femtocell Networks With Outage Constraints Based on Pricing Incentive Mechanism

Wireless services are developing rapidly and user requirements also are becoming more demanding. Femtocell networks have great potential in many aspects, especially in expanding the capacity and increasing the coverage of traditional cellular networks. However, it is challenging to motivate femtocell base stations (FBSs) to voluntarily adopt a hybrid access strategy to provide services and access to macrocell users (MUEs). In order to maximize the transmission rate of users, we propose an incentive mechanism in two-tier femtocell networks including a macrocell and multiple femtocells that share the spectrum. In the proposed mechanism, the macrocell base station (MBS) attempts to provide femtocells with a reward by pricing the transmission rates of the accessed MUEs, which are guaranteed by the FBSs. A Stackelberg game is developed to maximize the utility of the MBS and FBSs, and to guarantee the quality of service (QoS) of different users. An uncertain channel gain is formulated in the optimization problem and the uncertainty is restricted by a probabilistic constraint. Furthermore, a power control and nonuniform price bargaining algorithm is proposed to satisfy practical operation and obtain an optimal solution. Finally, numerical results validate the effectiveness of the proposed algorithm in terms of transmission rate improvement and outage reduction.