Design and Development of Energy Efficient Spectrum Sharing Algorithm for Cognitive Radio Networks and its FPGA Implementation

Abstract

Spectrum scarcity and congestion has motivated new communication paradigm to exploit the existing wireless spectrum opportunistically. An emerging technology based on cognitive radio, has the potential to maximize spectrum usage efficiently. Cognitive radio offers a flexible and efficient utilization of radio frequency resources by dynamic spectrum sharing as required in NextGen (5G) architecture of wireless communication. newlineThis thesis focuses on resolving the issue of spectrum scarcity and underutilization by newlineusing cognitive radio technology. Experiments have been carried out for cognitive radio newlinebased spectrum sharing wherein spectrum sensing is performed by energy detection newlinetechnique and spectrum allocation is based on a cooperative game theoretic model. newlineEnergy detection by periodogram and Welch method provided the power spectral density newlineestimates for monitoring the unused frequency bands or spectrum holes. The Neyman- newlinePearson hypothesis is considered for detecting the presence and absence of user signal, newlineover a bandwidth of 5MHz, with probability of detection and probability of false alarm as newlinemetrics. The real time implementation of algorithm has been done on Wireless Open newlineAccess Research Platform (WARP). The performance of various modulation schemes viz. BPSK, QPSK and 16-QAM are presented and discussed for improved signal quality. The newlinesystem performance is also investigated under different fading channels in order to study newlinethe qualitative and quantitative behavior of the developed technique under different newlinepropagation environments. Based on the sensing results, the secondary users have newlineinformation about the channels that they can access. Contd....