In this paper, we present a novel cyclic-shifted preamble which is suitable for use in synchronization in orthogonal frequency division multiplexing (OFDM) wireless local area networks (WLANs). Based on the novel cyclic-shifted preamble, we proposed two improved symbol timing estimators and a joint estimation method for carrier frequency and sampling clock offsets. It is shown that by simulations, the proposed scheme with low hardware complexity has a significantly improved performance than the other methods when a reasonable signal-to-noise ratio (SNR) is considered.