Performance analysis of cognitive WiMAX network for various MCS

Cognitive Radio has become a popular topic of research in recent years. It allocates the under-utilized spectrum dynamically to a group of Secondary Users (SU) which, in turn, enhances the Spectral Utilization considerably. Secondary or Cognitive Users identify suitable idle channels for transmission and utilize it opportunistically, until the Primary User reappears. However, channel conditions in wireless networks are time-dependent and vary with time. Hence, for any wireless network, a suitable Modulation and Coding Scheme (MCS) must be adopted (depending upon the channel conditions) for smooth data transmission. The present work analyzes the performance of a QoS aware Cognitive WiMAX network for various MCSs in order to maximize the spectral efficiency of a system. The focus of the present work is to analyze the spectral efficiency of the system under various MCSs. The effectiveness of the system has been observed based on the spectral efficiency for various MCSs by exhaustive simulation. The results show that maximum spectral efficiency has been observed for 64 QAM-5/6.