Local Connectivity of Cognitive Radio Ad Hoc Networks

We investigate the local connectivity of cognitive radio ad hoc networks (CRAHNs), i.e., node degree and probability of node isolation. The local connectivity of CRAHNs depends on not only its own network parameters but also the primary networks. To analyze the local connectivity, we use stochastic geometry and probability theory to derive the distribution of node degree, probability of available spectrum and probability of node isolation of the Secondary Users (SUs). The relation between the local connectivity of CRAHNs and the parameters of both primary and secondary networks is given. Theoretical analysis and simulation results indicate that the average node degree of SUs scales linearly for increases in the density of SUs with the slope determined by the density of Primary Users (PUs). It also indicates that the SUs' node isolation probability is largely determined by the density of PUs.