Cognitive radio (CR) is a technological invention to improve the spectrum performance in wireless networks linked to a cooperative spectrum sensing strategy. This performance, however, can be degraded by adversary secondary nodes which intentionally aim to falsify the decisions on the presence of primary nodes. The purpose of this paper is to model and investigate the impact of adversary secondary nodes in the context of cooperative spectrum sensing in CRs in terms of false alarms and missed detection probabilities. The impact of these probabilities is then included analytically in the throughput formula accordingly, under the assumption of adopting Slotted-ALOHA protocol by the secondary nodes. Then an intrusion detection system is proposed with the goal to maximize the network throughput with adversary secondary users. Simulations are carried out to test the validation of the proposed method and to evaluate the achieved results with the well-known decision rules.
