SAMAR - Spectrum Aware token MAc for cognitive Radio networks

Cognitive radio network (CRN) is one of the prominent technology for the next generation wireless networks. Due to the CR version, the users were classified into two types which are the primary users (PUs) and secondary users (SUs) which are also named as licensed and unlicensed users. The main objective of CRN is to access the underutilized licensed bands of PUs by SUs without any interference to the PUs transmission. In the CR technology, medium access control (MAC) plays a vital role to increase the spectrum efficiency and also minimize the collisions among SUs. So to design an efficient MAC is one of the significant challenges in the CRN. The existed MAC protocols are unable to identify the most appropriate spectrum to access. Thus, spectrum aware token based MAC protocol is proposed to resolve the spectrum selection issue in MAC design for CRN. In this paper, we consider expected spectrum stability time (ESST) as a metric to assign ranks to the available licensed spectrum bands. Simulation results for various parameters show that SAMAR protocol can approximately improve throughput 8% decrease transmission delay 75% compared with IEEE 802.11n. The remaining metric results have demonstrated the performance of existed MAC protocols like IEEE802.11n and TMAC with the proposed MAC.