CUCB-MAC: Channel Usage and Collision Based Medium Access Control Protocol for Cognitive Radio Networks

Cognitive Radio Networks (CRNs) allow their unlicensed users named Secondary Users (SUs) to share and access licensed wireless spectrum band without any kind of interference with its original users named Primary Users (PUs); and under condition that the PUs' Quality of Service (QoS) won't degrade. Due to the large number of SUs and as all of them will have the right to access the available spectrum band; a spectrum sharing protocol must be added in order to divide the available spectrum band fairly among these SUs. Spectrum sharing is similar to Medium Access Control protocol MAC in the current systems. This paper proposes a scheduling protocol named Channel Usage and Collision Based MAC protocol (CUCBMAC); this protocol is a slotted one that depends on 1) counting the number of collisions for each SU, 2) predicting the ideality of the entire available channels then 3) excluding some of the available channels at each time slot before allocating channels to SUs. It has been proved that the performance of the proposed CUCBMAC protocol overcome the performance of the Collision Based MAC protocol (CB-MAC).