Cognitive Radio Resource Management for QoS Guarantees in Autonomous Femtocell Networks

Deploying femtocell networks embedded in the Macrocell coverage greatly benefits communication quality in variety manners. However, the lack of schemes to effectively mitigate detractive interference, fully utilize radio resources and provide quality-of-service (QoS) guarantee (in terms of delay) creates challenges to practically facilitate the concept of femtocell. To tackle these challenges to achieve a successful dense femtocell deployment, this paper proposes a cognitive radio resource management (CRRM) scheme which is inspired by the spirit of cognitive radio technology. Instead of the need of a centralized manner, the femtocell with the proposed CRRM can autonomously sense the radio resource usage of the Macrocell so as to mitigate interference. By analytical deriving the effective capacity of the CRRM that specifies the QoS guarantee capability of the system, the optimum sensing period and radio resource allocation are proposed for the CRRM to achieve a fully radio resource utilization while statistically guaranteeing the QoS of the femtocell. Numerical results demonstrate that the proposed CRRM outperforms the randomized scheme (without CRRM) in terms of the radio resource utilization efficiency. Simulation results also support the effectiveness on the delay guarantee performance.