The Primary Exclusive Region in Cognitive Networks

Abstract

In this paper, we consider a cognitive network in which a single primary transmitter communicates with primary receivers within an area of radius RO, called the primary exclusive region (PER). Inside this region, no cognitive users may transmit. Outside the PER, provided that the cognitive transmitters are at a minimal distance isinp from a primary receiver, they may transmit concurrently with the primary user. We determine bounds on the primary exclusive radius RO and the guard band isinp to guarantee an outage performance for the primary user. Specifically, for a desired rate CO and an outage probability beta, the probability that the primary user's rate falls below CO is less than beta. This performance guarantee holds even with an arbitrarily large number of cognitive users uniformly distributed with constant density outside the primary exclusive region.