Capacity of cognitive radio multiple-access channels in dynamic fading environments

In this paper, the capacity of cognitive radio multiple-access channels (CR-MAC) with spectrum sharing property over dynamic fading environments is studied. In the system model, multiple secondary users (SUs) transmit to the secondary base station (SBS) under the transmit power (TP) and interference temperature (IT) at the primary base station (PBS) constraints. A theoretical fading model called hyper fading model, proposed in, that is suitable to the dynamic nature of cognitive radio channel is considered. The optimal power allocation method is utilized to maximize the capacity of CR-MAC for dynamic fading channel with TP and IT constraints and full channel side information (CSI). Numerical results are presented to verify the theoretical analysis and investigate the effects of average TP and IT on the capacity.