Downlink Resource Management Based on Cross-Cognition and Graph Coloring in Cognitive Radio Femtocell Networks

Femtocell technology features prominently in future communication system owing to its characteristic advantages. However, the coexistence of femtocells and traditional cellular system causes severe contradictions between spectrum utilization and interference. This paper studies the cross tier resource management and intra tier resource management in hybrid macro/femto network, and a novel Cross-Cognition scheme for cross tier resource management is proposed in order to achieve better spectrum utilization and lower interference. Moreover, a resource allocation scheme based on graph Coloring is also proposed for intra tier resource management to decrease the intra tier interference. Simulations show that the proposed schemes significantly increase the throughput of femtocell system, and outperform traditional cognitive resource allocation schemes.