One-shot subspace based method for blind CFO estimation for OFDM

In this paper, we propose a novel subspace based approach for blind carrier frequency offset estimation in OFDM. Correlation in squared spectrum of the channel is exploited and low rank signal model is thereby obtained without virtual subcarriers. The proposed estimator accomplishes frequency synchronization with a single OFDM block. No extensive time averaging is needed, which makes the approach very attractive for time and frequency selective channels where the offset may be time varying. The method is statistically very efficient since close to optimal performance is achieved with respect to the Cramer-Rao bound with a single block.