The Primary Exclusive Region in Cognitive Networks
Mai H. Vu, Natasha Devroye, Vahid Tarokh · 2008
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 isinpfrom a primary receiver, they may transmit concurrently with the primary user. We determine bounds on the primary exclusive radius ROand the guard band isinpto guarantee an outage performance for the primary user. Specifically, for a desired rate COand an outage probability beta, the probability that the primary user's rate falls below COis 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.