Connectivity of interference limited cognitive radio networks

This paper considers the connectivity of cognitive radio networks, which is defined as the existence of an infinite connected component of secondary users. The connectivity reveals the possibility of communication between an arbitrary pair of nodes in the secondary network, while long range communication is achieved in a multi-hop fashion. In their seminal work, Wei Ren et al. introduce the concept of connectivity region, and characterize some basic properties based on the Poisson Boolean model. In this paper, we take interference into consideration and study the impact of interference to the connectivity of the secondary network. Using methodologies of stochastic geometry and percolation theory, we find that the connectivity region without taking interference into consideration is a subset of our connectivity region, which means interference will not adversely affect the connectivity of secondary network. Specifically, as long as the density pair of the two networks lies in the connectivity region established in the Poisson boolean model, there must exist an orthogonal factor γ which guarantees the connectivity of the interference limited secondary network.