New joint frame synchronisation and carrier frequency offset estimation method for OFDM systems

We propose a new joint frame synchronisation and carrier frequency offset estimation scheme for burst transmission mode OFDM systems. This scheme uses a central-symmetric and comb-like (CSCL) training sequence, which eases the power detection at the receiver without increasing the total training sequence power. Fine frame synchronisation as well as carrier frequency offset acquisition with a maximum acquisition range of ± N/4×SF times the sub-carrier spacing can also be performed based on the proposed CSCL training sequence, where N is the discrete Fourier transform (DFT) length and SF is an integer-valued spreading factor used to generate CSCL. The post-acquisition residual carrier frequency offset can be further estimated and corrected via a fine adjustment algorithm. In order to reduce performance loss due to the high peakto- average power ratio (PAPR) of the CSCL training sequence, a time-domain constant-envelope (CE) training sequence is also proposed. The superior estimation accuracy of the proposed algorithm over that of the Moose algorithm and the SS (Shi and Serpedin) algorithm is proved by computer simulation.