Analysis of priority queueing with multichannel in cognitive radio network

Since there is an ever-increasing demand of bandwidth, spectrum management is the key to provide sufficient spectrum for various services. In this way, networks employing dynamic spectrum access are identified for handling the underutilization issues. In this paper, a network consisting of cognitive radio is investigated. The system is modelled based on the M/D/1 system with priority queueing. Different approaches, preemptive and non-preemptive priority queueing, have been used for these models. Non-preemptive priority shows an improvement of about 32% (at small arrival rates) for the primary user and up to 38% for the secondary user, and with the preemptive priority, there is 19%-42% and up to 33% (at small arrival rates) reduction in the primary user and secondary user waiting times respectively. Furthermore, a multichannel system, the M/D/s model is proposed and it is also investigated with the preemptive and non-preemptive priority queueing. The non-preemptive model shows a decrease in the secondary user waiting time, by allowing it to effectively occupy the time slots without affecting the primary user transmission. Moreover, the primary user waiting time is reduced by means of the preemptive model.