Abstract: According to the dynamic heterogeneity of available channels and scarcity of global common channels in cognitive radio Ad-hoc networks(CRAHNs)，a distributed clustering algorithm CRAP-CMI(Clustering Based on Affinity Propagation with Controlled Message Interchanges) was proposed. Based on the interchange and update of messages among neighboring nodes, cluster structure was constructed on the channels shared by most local neighbors with the nodes holding most available channels as cluster heads. To reduce the clustering overhead as well as adapt to the variadons in CRAHNs, CBAP-CMI refines the number of messages interchange and achieves rapid distributed clustering.The simulation results show that the proposed algorithm reduces the number of clusters and increases the average available channels for each link and the common channels in each cluster, providing an efficient topology for distributed spectrum cooperation in CRAHNs.

Key words: Cognitive radio Ad-hoc networks,Clustering,Affinity propagation,Robustness