Frequency and time synchronisation of an ofdm receiver by means of maximum likelihood decoding

摘要

A method for frequency and time synchronization of a receiver for receiving Orthogonal Frequency Division Multiplexing (OFDM) signals is described. A quality criterion of a OFDM signal is determined during one of the frequency intervals (hops) for each point of one of the two-dimensional frequency and time search areas. The area point having the optimum quality criterion (tau_x, f_x) of the OFDM signal is then determined on the basis of said quality criterion, and the receiver is synchronized on the nominal frequency in view of the different between the nominal frequency (f₀) and the frequency value (f_x) corresponding to the optimum quality criterion. The OFDM signal may be demodulated and decoded starting with the time value (tau_x) corresponding to the optimum quality criterion.