A novel OFDM synchronization algorithm based on CAZAC sequence

Abstract

A novel synchronization algorithm based on training sequence is proposed for OFDM systems. Different from the existed algorithms with a symmetric training sequence, it uses the training sequence consisting of one CAZAC sequences with the same length and nonsymmetrical structure. The proposed method firstly uses the property of good self-correlation and constant amplitude of the CAZAC sequence to get the coarse timing and fractional frequency offset, and then uses the relation between the deviation of the coarse timing and the frequency offset for the fine timing and frequency offset estimation. Computer simulation results show that the performance of the proposed algorithm is much better than the existing ones in terms of timing and frequency accuracy, and that the frequency offset estimation range is up to the whole channel band. Moreover, when the SNR is high, the MSE of the frequency offset estimation approaches to the Cramer-Rao Bound.