A Novel Approach towards Channel Allocation in Cognitive Radio Networks

Abstract

The Cognitive Radio (CR) is an intelligent and innovative communication proficiency in wireless communication system which affords a keen solution to the insufficiency of spectrum utilization in Cognitive Radio Networks (CRNs). The primary goal of CR is to improve the Secondary Users (SUs) spectrum utilization when Primary Users (PUs) temporarily become idle.  The existing static allocation such as spectrum and channel allocation leads to spectrum scarcity. The existing CR Medium Access Control (CR-MAC) protocols have issues like packet-delay, packet-collisions and Quality-of-Service (QoS) when channels are selected randomly. We formulate a CRMAC protocol based upon channel quality and to attain context cognizance and adaptive channel selection intelligence. The utility function of Channel Quality Indicator (CQI) is adopted with each channel in CRN to determine the channel quality. The best quality of channel is favored the Common Control Channel (CCC) and dynamically changed in each round. Omni-directional Cognitive Function based on Slots (CFS) is used to maintain the transmission control Time Division Multiple Access (TDMA).  The data transmission is managed by using a Distributed Synchronization Function (DSF) on directional antenna.  The priorities are assigned based on the channel weights respectively. The higher weighted channels are assigned to higher priority. The proposed hybrid MAC based channel quality protocol has minimized congestion and delay using NS-2 simulation.