Nonquiet primary user detection scheme

This paper proposes a nonquiet primary user detection scheme in cognitive radio networks. This scheme can realize cyclostationary feature detection on the condition that the secondary user has same classification and cycle frequency as the primary user. At first, the linear prediction was utilized to predict the signal of secondary user in order to reduce its effect on spectrum sensing. The residual signal will be gained by means of the received signal subtracts the predict signal. After that, by calculating the autocorrelation function of residual signal and compare it with the threshold, the nonquiet primary user detection scheme will be realized. In this method, quiet period is not needed so that the transmission performance can be improved without the interruption of on-going transmission. Simulation result shows that the proposed scheme can realize nonquiet spectrum sensing in the low SNR environments when the secondary user has the same classification and cycle frequency as the primary user.