On the use of double correlation for frame synchronization in the presence of frequency offset

A new frame synchronization technique, which is robust to carrier frequency and phase errors, is proposed for M-ary PSK systems. This technique is derived through some modification of the procedure for obtaining the maximum likelihood (ML) rule in Gansmann et al. (1997). The proposed rule is based on an operation called double correlation, which evaluates the correlation after properly multiplying the received signal with a sync pattern. It is shown through computer simulation that the proposed rule outperforms the existing ML rule when the frequency offset is greater than about 0.02/T.