This paper deals with detection of weak cyclostationary signals embedded in colored Gaussian noise. We consider the normalized correlation function of the noise to be known and the noise power to be unknown. We propose a temporal structure of the single cycle detector which includes a prewhitening filter. We compare the performance of this detector to the classical radiometer and the modified radiometer. The performance is quantified in terms of receiver operating characteristics for two different noise power spectral densities. We compute the theoretical deflection, this measure gives a means to choose the best cyclic frequency used in the single cycle detector. We conclude that cyclic methods outperform radiometric methods when the noise and the signal power spectral densities strongly overlap and for a unknown noise power