Preamble-based Symbol Timing Estimation for Wireless OFDM Systems

We propose a timing estimation scheme that reduces computational complexity while achieving performance comparable to the autocorrelation method commonly employed at the wireless receiver. The proposed method is based on the average magnitude difference function (AMDF). We present performance results for the proposed method for AWGN and Raleigh-fading channels in the context of IEEE 802.11a short preamble sequence. We also propose a preamble sequence based on Golomb sequence and compare its timing estimation performance with the IEEE 802.11a short-sequence. Simulation results show significant performance improvements for AWGN as well as Raleigh-fading channels.