DCCC-MAC: A Dynamic Common-Control-Channel-Based MAC Protocol for Cellular Cognitive Radio Networks

摘要

We propose a novel dynamic common-control-channel-based medium access control (DCCC-MAC) protocol for cellular (centralized) cognitive radio (CR) networks. Specifically, unlike the traditional dedicated-control-channel-based medium access control (MAC) protocols, the proposed MAC protocol eliminates the requirement of a dedicated channel for control information exchange. During a given transmission frame, the common control channel (CCC) is selected by a cooperating set of secondary users (SUs) by using a support-vector-machine (SVM)-based learning technique. In the DCCC-MAC protocol, the frame duration is divided into four main phases as follows: spectrum sensing, CCC selection, data transmission, and beaconing. The SUs that participate in the CCC selection process are allocated channels for data transmission during a frame interval using a scheduling process, whereas the other SUs have to contend to access the channels. We present an analytical approach to calculate the minimum required number of minislots in the transmission frame for a given number of SUs in the CCC selection process. The saturation throughput of the proposed MAC protocol is analyzed in closed form. To this end, the numerical and simulation results are presented to quantify the performance of the proposed DCCC-MAC protocol. We also compare the performance of the DCCC-MAC protocol with that of two other state-of-the-art CR MAC protocols that use CCCs.