Cross Layer Routing and Medium Access Control Protocols in Cognitive Radio Networks

Cognitive Radio technology was introduced as a possible solution to spectrum scarcity and underutilization of spectrum. Cognitive Radio Networks (CRN) consist of two types of users, the Primary Users (PUs) and the Secondary Users (SUs). PUs are licensed users of the spectrum and have full usage of the spectrum, while SUs are unlicensed users and can only use the spectrum opportunistically in the absence of PUs. However, the CRN technology ensures that the use of the licensed spectrum by SUs is non-interfering. The CRN through the Dynamic Spectrum Assignment (DSA) addresses the underutilization of the licensed spectrum bands. Due to this DSA approach, licensed spectrum bands can be utilised by the SUs and coexist with PUs in a non-interfering manner to improve spectrum usage. Routing problems in CRN degrades the performance of the network. For effective routing, routing protocols require spectrum sensing and related data to make sound and informed decisions. In this study, we propose an Optimised Cognitive Cross-layer Multipath Probabilistic Routing (OCCMPR), an optimised routing and Media Access Control (MAC) protocol in CRN-Cross Layer Design (CLD). The performance evaluation of this scheme is compared to existing Cognitive Ad-hoc On-demand Distance Vector (AODV) and Cognitive Cross-layer Multipath Probabilistic Routing protocols (CCMPR). The schemes were simulated using MATLAB installed in the Windows 10 operating system and the evaluation metrics are; energy consumed per packet band Packet Delivery Ratio (DPR). The simulations were performed under different scenarios and indicated that the OCCMPR outperformed the other schemes.