Impact of cooperative detection on primary system´s QoS in cognitive radio networks

The major concern of every spectrum sensing technique based cognitive radio networks is the accuracy of the detection. Cooperative spectrum sensing techniques exploit the diversity of the secondary users in order to enhance the reliability of the decision. In this context, fusion rules are required to derive a final decision based on the different secondary users´ decisions. In this paper, the impact of the cooperative spectrum sensing on the accuracy of the decision in terms of the probability of detection, mis-detection, false alarm and occupancy is studied. As well, the impact in terms of generated interference and achieved throughput is analyzed. AND, OR and Two witnesses rules are examined in this paper and performance through simulations is presented. Simulations results proved that a compromise between secondary users throughput and generated interference should be considered based on the distance between the primary and secondary base stations. If this distance is limited, two witnesses or AND rules offer better performances. However, OR rule offers better performances if this distance is important.