Diversity-Multiplexing Tradeoff in an Interweave Multiuser Cognitive Radio System

 Diversity-Multiplexing Tradeoff in an Interweave Multiuser Cognitive Radio System

In an interweave cognitive radio system, the spectrum sensing performance affects the rate and reliabilityof data transmission. In wireless communications, the tradeoff between the reliability and data rate can be evaluated by diversity-multiplexing tradeoff (DMT) analysis. In this paper, through the analysis of the error probability at the secondary receiver, we derive the DMT for the multiple-access channel and user-selection schemes in an interweave multiuser cognitive radio system considering the spectrum sensing effect on the rate and reliability. We show that the DMT of the system can be improved by cooperative spectrum sensing. Simulations also approve ouranalytical results.