Dynamic Spectrum Allocation MAC Protocol Based on Cognitive Radio for QoS Support

To address inefficiency of the spectrum utilization and the limited available spectrum band, cognitive radio has emerged as a significant solution. In this paper, we propose a novel MAC protocol in multi-channel wireless networks by using dynamic spectrum allocation (DSA) based on cognitive radio for QoS support. According to the user request, variable spectrum is allocated for quality of service (QoS) guarantee through DSA mechanism. Dynamic spectrum allocation is implemented with the procedure of FRQ/FRP/ACK-hello over a control channel, DATA/ACK over allocated data channels. For cooperative detection, a hello message is exchanged periodically to enhance the spectrum sharing in our MAC protocol. In addition, the results of performance evaluation demonstrate that the proposed DSA-MAC protocol improves the throughput significantly, as compared to the IEEE 802.11 MAC.