Supporting Real-Time CBR Traffic in a Cognitive Radio Sensor Network

In this paper we consider supporting real-time traffic in a cognitive radio sensor network (CRSN). A lot of traffic in wireless sensor networks (WSNs) requires strict quality of service (QoS) requirements, while most existing WSNs working in the license-free spectrum cannot provide guaranteed QoS. A cognitive radio network (CRN) can possibly support traffic with strict QoS requirements while avoiding high cost for accessing the licensed spectrum. The CRSN studied in this paper is cluster-based and supports both realtime traffic and best effort traffic. We consider two resource allocation policies in order to provide a higher priority to the real-time traffic. Mathematical models are developed to analyze the performance of the real-time traffic, and the analytical results are verified by computer simulations. Our results indicate that satisfactory real-time performance can be achieved in the CRSN.