Energy detection with different digital modulation techniques over Rayleigh fading channels in cognitive radio networks

The sensing of radio spectrum is an essential problem in cognitive radio(CR) networks, where secondary users (SUs) need to detect the presence of primary users (PUs) before they use the spectrum allocated to PUs. The detection of primary user status and the spectrum sensing are the major issues in cognitive radio systems. We employ one of the simplest and most efficient Spectrum Sensing technique, the Energy Detection(ED) with three different digital modulation techniques BPSK, QPSK, 16-QAM. In this paper, we analyze the performance of the Energy Detection technique with BPSK, QPSK, 16-QAM modulation techniques over Rayleigh fading Channel. Further, we analyze the performance and BER (Bit Error Rate) of ED under Rayleigh fading and AWGN channels. The investigation and analysis on Energy Detection with above digital modulation techniques can be utilized for future reference of spectrum sensing in the CR networks over AWGN and Rayleigh fading channels.