A Channel Allocation-Based Multichannel MAC Protocol for Cognitive Radio Networks

For the rapid development of the Internet of Things (IoT), the support of wireless technology is indispensable. The wide application of wireless technologies will pose new challenges to the spectrum resources. Cognitive radio (CR) has a wide range of application scenarios in IoT, which can effectively improve spectrum utilization and communication efficiency. Efficient medium access control (MAC) protocol design without reliance on a common control channel is a crucial concern in multichannel CR networks (CRNs). In this article, we propose a joint channel allocation and MAC framework for CRNs. The channel allocation matrix maximizes the average gain of the system users, and we also verify the effectiveness of the proposed algorithm. To ensure that the system throughput is maximized within the acceptable transmission delays between group leaders (GLs), we have designed a variable cyclic quorum system and group structure in the MAC protocol. Meanwhile, we analyze the average transmission delay and system throughput within the group and for the GL. The results show that the proposed protocol is beneficial for intragroup information transfer. The latency is reduced by around 40%–80% relative to the constant quorum system, while the saturation throughput of the system is increased by about 6%.