An adaptive structure of CR network under optimal sample number for accurate estimation

Spectrum sensing in cognitive radio network plays a vital role in the efficient utilization of underutilized licensed band. Efficient utilization implies that whenever spectrum is not being used by primary user it should be assign to secondary user. Conventional structure of spectrum sensing using energy detection technique cannot guarantee to fulfill the interest of primary user and secondary user simultaneously. Primary user wants to maximize the probability of detection whereas secondary user wants to minimize probability of false alarm. This paper analyzes an adaptive structure of spectrum sensing which is based on the trade-off between the interest of primary user and secondary user. Adaptive structure tries to minimize the probability of error in allocation of frequency band among primary user and secondary user. We derive an expression of optimum number of sample required which minimizes the probability of error, for accurate estimation at different parameter like SNR and α. The adaptive structure demonstrates the better utilization of frequency band by having better probability of detection and lesser probability of false alarm.