A new algorithm for admission control of secondary users in CDMA based Cognitive Radio Network

In this paper, a simulation study has been carried out to evaluate performance of a new call admission control algorithm for secondary users in CDMA based Cognitive Radio Networks (CRNs). Performance has been evaluated for secondary users (SUs) in an uplink scenario of CDMA network consisting of cognitive users or secondary users (SUs) and Base Station (BS). A primary receiver (PRx) is also assumed to be present in our network model. We assume a network where primary radio network (PRN) and cognitive radio network (CRN) coexist. The new algorithm for admission control of cognitive radio (CR) users considers two constraints. BS computes instantaneous SIR of a SU and PRx computes interference from all SUs present in the network. Specifically, the proposed CAC algorithm considers uplink Signal to Interference Ratio (SIR) of a SU to be above an SIR threshold level and instantaneous interference at primary receiver to be below a predefined interference threshold. Performance of the algorithm has been evaluated in different scenarios in terms of blocking probability of SU in presence of a PRx.