Co-operative spectrum sensing for cognitive radio systems with Nakagami-m fading channel

Spectrum Sensing is the basic and important operation in Cognitive Radio (CR) to find the unused spectrum. To detect the unused spectrum different types of detectors are used. Energy detector is among them and a popular sensing method because it doesn´t require transmitted signal properties, channel information, of even the type of modulation. When Cognitive Radio user experiences deep shadowing or fading effect, primary user detection is very less .In order to detect the primary user (PU) more accurately, we allow the CR users to cooperate by sharing their information. So we use Co-operative Spectrum Sensing technique which incorporate more number of users, to increase probability of detection. This study summarizes the performance result of energy detector over Nakagami-m fading channel and hard decision fusion techniques for Cognitive users. The performance is evaluated by means of Receiver Operating Characteristics (ROC) and Complementary Receiver Operating Characteristic (CROC) curves. It clearly shows that the probability of miss detection decreases and Probability of detection increases with the co-operation of more number of secondary users and also we investigate the effect of SNR over probability of detection.