Blind Carrier Frequency Offset Estimators Based on Variance for OFDM Systems

Carrier frequency offset (CFO) estimation is critical in practical orthogonal frequency-division multiplexing (OFDM) systems. In this paper, we propose two novel blind CFO estimators named the variance estimator (VE) and the approximate variance estimator (AVE) respectively with high bandwidth efficiency. Both of them are based on minimization of the variance of the received symbols on each subcarrier, but the AVE only utilizes a half of OFDM symbols needed in the VE at the cost of a little degradation in performance. Simulation results show that the proposed estimators are attractively efficient for the future wireless communications.