A blind frequency offset estimator for OFDM/OQAM systems

Like other OFDM-like systems, OFDM/OQAM systems are very sensitive to carrier frequency offset. A new blind carrier frequency estimator is introduced herein for OFDM/OQAM systems by exploiting the noncircularity of the received signal. Since the received signal exhibits conjugate cyclic frequencies at twice the carrier frequency offset, a frequency estimator is proposed by maximizing a cost function expressed in terms of the sample conjugate cyclo-correlations. Computer simulations illustrate that the proposed estimator is very accurate whenever large observation windows are available, is robust to timing errors and frequency-selective fading effects.