Dynamic Spectrum Allocation in Cognitive Radio: Throughput Calculations

In this paper, we use queuing theory (egalitarian process sharing) to derive throughput expressions for dynamic spectrum allocation in cognitive radio systems. In particular, we consider different priority groups, for example, secondary users who can access the channel only if no primary user is active. The aggregated throughput, a measure for social optimality, is also investigated. Moreover, we calculate the user throughput for the case that two network operators share their spectrum by cognitive radio technologies. Primary users of operator 1 are then secondary users of operator 2 and vice versa. The optimal load distribution between primary channel and secondary channel is given by the Nash equilibrium.