Robust timing and frequency synchronization based on constant amplitude zero autocorrelation sequence for OFDM systems

In this paper, we propose a robust timing and frequency synchronization algorithm for the orthogonal frequency division multiplexing (OFDM) systems. The algorithm we proposed can achieve accurate timing and frequency synchronization in time-domain by using the preamble consisting of only one training symbol based on constant amplitude zero autocorrelation (CAZAC) sequence and a new weighting factor. The timing metric used in the algorithm has a peak only at the correct starting point while almost zeros at other points. So the “platform effect” can be avoided and a high timing precision can be obtained. Meanwhile, the proposed method of integer frequency offset estimation is robust to the multipath and noise interference. Computer simulation results show that our proposed scheme achieves superior performance under the multipath fading channel than existing algorithms in terms of timing and frequency synchronization.