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Modeling and analysis of opportunistic spectrum sharing with considering access strategy

We analyze the performance of an opportunistic spectrum sharing (OSS) system with considering the access strategy of both types of users (primary users and secondary users). In the OSS system, the secondary users (SUs) detect channels which are unused by primary users (PUs) and utilize these channels to transmit data. An ongoing SU also detects the PUs' arrival and then either switches to another idle channel or comes into a buffer. We propose an access strategy for SUs to match the access behavior of PUs. Then, we adopt the access rule transition matrix to model the access behavior for each type of user and apply it into the continuous-time Markov chain model. Numerical results show that the buffer for SUs helps maximize the total carried traffic. And the matching of the two access strategies can significantly improve the quality of service (QoS) of SUs, in terms of the mean number of spectrum handoff. Finally, the numerical results are verified via OPNET simulations.