We present the joint maximum likelihood (ML) symbol-time and carrier-frequency offset estimator in orthogonal frequency-division multiplexing (OFDM) systems. Redundant information contained within the cyclic prefix enables this estimation without additional pilots. Simulations show that the frequency estimator may be used in a tracking mode and the time estimator in an acquisition mode.
['J.J. van de Beek', 'Magnus Sandell', 'Pål Börjesson']
ML estimation of time and frequency offset in OFDM systems