Throughput Optimization and Energy Efficient Cooperative Spectrum Sensing Based on a Group of Sensors in Cognitive Networks

Abstract

A technology that deals with the spectrum scarcity and underutilization is cognitive radio (CR), where by spectrum sensing is one of the most important aspects. Multiple sensors perform cooperative spectrum sensing to reduce shadowing and multipath fading in the network. Due to the limitations of energy in sensors, energy efficiency emanate as significant issue in sensor-aided CR networks. Scheduling of each group of sensor active time can definitely reduce energy consumption and boost network life time. The sensors are divided into groups depending on the geographical position, only one group of sensors is turned on at a time while maintaining the necessary detection and false alarm thresholds. Each group is activated independently and non-activated are set in a low energy sleep mode to boost the network lifetime. Also throughput optimization is achieved by increasing the bit rates of data received to the fusion center which decrease the reporting time of secondary users. Analysis and simulation are presented by considering the performance of energy detection which discovers spectrum holes or white spaces and cooperative spectrum sensing approaches by using AND, MAJORITY and OR rule.