Outage probability analysis for cognitive radio network caused by primary users

Cognitive radio systems offer the opportunity to improve spectrum utilization while avoiding the interference to primary users. On the one hand, secondary users must be aware of the interference caused to primary users. Therefore, cognitive radio network should control their transmission power. On the other hand, the interference from primary network may degrade the performance of cognitive network. This paper considers the outage probability of cognitive radio network coexisting with primary users. A closed-form outage probability is derived for cognitive network with two nodes. The outage probability is mainly determined by the interference from primary users.