Energy detector threshold under White Gaussian Noise channel in cognitive radio system

Energy Detection is a popular technique to detect primary user (PU) in cognitive radio (CR) compared with others. Due to less complexity and easier to be implemented makes energy detector (ED) is a common technique in use for signal detection. This paper studies detection performance of primary signal under Additive White Gaussian Noise (AWGN) with low signal to noise ratio (SNR). The performance of ED is evaluated through receiver operating characteristic (ROC) curve with probability of detection (P_D) and probability of false alarm (P_F) as a metric. Then, probability of detection as a function of energy threshold is further studied. The derived results show that increasing the degree of energy threshold decreases detection performance in term of probability of detection.