PERFORMANCE ANALYSIS OF COGNITIVE NETWORK WITH PRIMARY AND SECONDARY CHANNELS

Abstract

Abstract. We consider a cognitive network with a primary and a sec-ondary channel. Primary users have higher priority on the usage of theprimary channel, and secondary users are allowed to opportunisticallyaccess the primary channel at times when the channel is not occupiedby primary users. The secondary channel is dedicated only to secondaryusers. An analytical model is presented to obtain the performance ofan opportunistic spectrum access using both the primary and secondarychannels, and is validated by simulations. 1. IntroductionReports of spectrum eciency reveal that a considerable region of the spec-trum remains unused. As a solution for such inecient spectrum usage, op-portunistic spectrum access (OSA) has been intensively studied. Under thissystem, a secondary user that does not have a license to use the spectrum isallowed to opportunistically occupy an idle spectrum band owned by a licenseethat is termed by the primary user [1, 2]. Much attention has been paid to thequality-of-service of secondary users. Wang et al. [3] proposed two cognitiveMAC schemes to support voice services in the presence of primary users. Lee[4] developed a simple approximate model for unslotted OSA networks undernon-saturation conditions. Considering prioritization among secondary users,Lee [5] proposed an OSA scheme with channel reservation for high prioritysecondary users and bu ering for low priority secondary users.This paper considers a cognitive network with a primary and a secondarychannel. Primary users have higher priority on the usage of the primary chan-nel, and secondary users are allowed to opportunistically access the primarychannel at times when the channel is not occupied by primary users. Thesecondary channel is dedicated only to secondary user. The main objective of