Minimum Interference Topology Control in Cognitive Radio Networks through Channel Assignment
Abhinav Ralhan, Ram Narayan Yadav, Rajiv Misra · 2018
Connectivity is a fundamental problem in wireless network. Connection between any two random nodes in a cognitive radio ad hoc network cannot be determined by their distance and transmission powers only. It also depends on the whether they have common available channel to open for communication. Due to primary users' (PUs') activities, the nature of available spectrum is non-homogeneous and dynamic. To realize a link between two different secondary users (SUs) in a cognitive radio network (CRN), channels assigned to links incident on the nodes must be present in their available channels set called channel constraints. A SU can open a limited number of channels simultaneously due to limited number of radios, called radio constraints. These constraints make the problem of realizing connected topology in CRN a challenging task. Here, we study the problem of network connectivity with minimizing network interference by satisfying the radio constraints and channel constraints, called minimum interference topology control problem (MITCP). First, we show that MITCP is NP-hard and then present a distributed algorithm using the concepts of maximum clique and graph coloring algorithms to address this problem. We have shown through results that our proposed algorithm generates a topology with reduced network interference.