An Improved Timing Synchronization Method for Broadband OFDM Based Power Line Communication

In this paper, we analyze the timing synchronization for OFDM based broadband power line communication (PLC) systems. Four classical methods are studied over a PLC channel. Based on detailed performance comparison and complexity analysis, this paper proposes an improved method, which uses a repeated-conjugated-centrosymmetric preamble and consists of two stages, namely, coarse estimation and fine estimation. By the proposed method, the estimation accuracy in low SNR (signal-to-noise ratio) condition is significantly improved. In addition, an implement scheme adaptive to SNR changes is presented and applied to the proposed method to get further complexity reduction. Simulations validate that, with relatively less computation, the proposed algorithm has a much smaller mean square error (MSE) in the SNR range from 0dB to 14dB.