Modeling and performance analysis of cognitive radio systems from a deployment perspective

Abstract

A cognitive radio (CR) system aims at an efficient utilization of the spectrum below 6 GHz - suitable for mobile communications - by enabling a secondary access to the licensed spectrum while ensuring a sufficient protection to the licensed users. Despite the fact that an extensive amount of literature has been dedicated to the field of CR, its performance analysis has been dealt inadequately from a deployment perspective, therefore making it difficult to understand the extent of vulnerability caused to the primary system. Following a deployment perspective, it has been identified that the involved channels' knowledge is pivotal for the realization of CR techniques. However, the aspect of channel knowledge in context of CR systems, particularly its detrimental effect on the performance, has not been clearly understood.With the purpose of curtailing this gap, this chapter proposes a successful integration of this knowledge by carrying out estimation of the involved channels within a CR system. More specifically, this chapter outlines the following two aspects: first, this chapter establishes an analytical framework to characterize the degradation in the performance due to effects such as time allocation and variation, arising due to imperfect channel knowledge. Second, this chapter features performance tradeoffs that determine the maximum achievable throughput of the CR systems while satisfying the interference constraint.