Refined Two-Step Energy Detection Methodology for Channel Sensing based on BER Calculations

Spectrum sensing for Cognitive Radio (CR) determines the availability of the spectrum, from which communication parameters like modulation techniques, protocol, transmission time can be optimised for the current channel. This paper proposes a refined two-step methodology of spectrum sensing that involves both energy detection as well as the actual testing of the channel; the combined results of which are used for Primary User (PU) detection. The proposed scheme of testing has a superior Probability of Detection of a PU, as compared to conventional energy detection methods, especially in hidden and exposed node scenarios. Practical results measured using USRP boards verified the improved results obtained from simulation.