An Energy-Aware Robust MAC Protocol for Prolonging Network Lifetime in Cognitive Radio Sensor Networks

A cognitive radio sensor network (CRSN) is a wireless sensor network (WSN) with cognitive radio capabilities that ensures efficient spectrum management. In general, CRSNs facilitate the combined use of unused licensed frequency spectrum and unlicensed frequency spectrum. Prolonging network lifetime is very important in the design of a medium access control (MAC) protocol in CRSNs because additional energy for spectrum sensing and dynamic spectrum access is required, in comparison to conventional WSNs. In this paper, an energy-aware robust MAC (ER-MAC) protocol for prolonging network lifetime in CRSNs is proposed, in which the network lifetime is increased by reducing collisions and adjusting sensing interval. Furthermore, the number of retransmissions is reduced by utilizing more reliable channels. Simulation results show that the proposed ER-MAC outperforms the conventional protocol in terms of network lifetime.