This paper discusses a new timing synchronization technique for OFDM systems which uses no special symbols such as null nor charp symbols. In the technique, the timing phase is detected by the peak position of the autocorrelation of the received signal. An IIR filter is used to have a suitable shape of the autocorrelation so that the peak position can be easily detected with accuracy under poor channel conditions. Additionally, the timing frequency offset detection is realized by a simple FIR filter which detects the moving direction of the peak position. Hardware experimental results show that the mean acquisition time is less than 0.4 sec, where the acquisition time is defined as the necessary time to have a same peak position of the autocorrelation in the period of 3M (=96) consecutive symbols. Almost same results have been observed even in multipath, flat fading, and multipath fading channels.
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