Spectrum-Aware Clustering with Proactive Handoff for Distributed Cognitive Radio Ad Hoc Networks

To improve the transmission performance, cluster structure is constructed for large scale cognitive radio ad hoc networks (CRAHNs). However, dynamic spectrum access (DSA) and blind information environment in CRAHN make the clustering design extremely challenging. To solve this problem, we propose a novel clustering algorithm to construct and maintain the cluster structure. The proposed spectrum-aware clustering algorithm is designed to maximize common channels inside a cluster and to minimize common channels between adjacent clusters. To maintain the cluster architecture, we propose a proactive channel handoff scheme to reduce the interference with PUs. The simulation results show that the constructed clusters have more intra-cluster common channels and less inter-cluster common channels. And the proposed handoff scheme can adjust to the changing PU activities.