A New Symbol Timing and Frequency Synchronization Design for OFDM-based WLAN Systems

In this paper, we present a new symbol timing and frequency synchronization method for OFDM WLAN system. A new method for synchronization using preamble structure of the IEEE 802.11a is proposed. The consecutive preamble structure is exploited to find the symbol starting-point and frequency offset accurately even under low SNR. The proposed timing synchronizer performs the fine timing synchronization first, and recognizes the end of short training symbol by coarse timing synchronization. The new frequency synchronization which means the estimation of frequency offset is more accurate than conventional method by considering the amplitude of preamble samples. Simulations show that it has distinct advantage over the conventional methods under multipath wireless channel condition even though it uses the fixed threshold for decision.