Spectrum management scheme for heterogeneous cognitive radio networks

Abstract

Abstract-In cognitive radio networks (CRNs), opportunistic spectrum access (OSA) has been referred to as a solution to overcome the spectrum scarcity problem and to produce a better utilization of the existing licensed radio spectrum. The OSA spectrum management concept gives the secondary users (SUs) the opportunity to access unused parts of the licensed spectrum owned by primary users (PUs). In CRNs, the SUs are greatly suffering from the PUs activities. To reduce the impact of the PUs, we propose a spectrum management scheme over a non-homogenous spectrum environment (i.e. licensed and unlicensed) to improve the performance of the SUs. In the proposed scheme, different types of buffers are utilized to decrease the blocking probability for newly arriving users and dropping probability for ongoing connection as well as improving the throughput of SUs. An analytical model based a multi-dimensional continuous-time Markov chain and a level dependent quasi-birthdeath is introduced from which the aforementioned performance metrics are derived.