A Cross-Layer Design of Channel Assignment and Routing in Cognitive Radio Networks

Cognitive Radio (CR) technology provides a new and promising solution to improve the spectrum utilization. Due to the dynamic and diversity characteristics of channels in Cognitive Radio Networks (CRNs), channel assignment and routing paths selection are critical issues for the functionality and performance of CRNs. In this paper, the routing metric of Minimum cumulative Interference and channel Switching Delay (MISD) is proposed for CRNs, which jointly undertakes the intra/inter-flow interference and channel switching delay for the end-to-end route. With consideration of the diversity of Spectrum OPportunity (SOP) set for each cognitive user, the optimal end-to-end path and channel on each hop are found in route resolve procedure by cross-layer design among the physical layer, MAC layer and network layer. Simulation results show that the proposed routing metric outperforms minimum hops metric and Weighted Cumulative Expected Transmission Time (WCETT) metric in terms of network throughput, end-to-end delay, packets delivery ratio and route overhead in CRNs.