Abstract: Aiming at the real application of OFDM signals’ parameter estimation and demodulation, a method is proposed for the accurate estimation of the symbol rate. The OFDM sub-carriers, accurately estimated by the high-order cyclic cumulants, are used to construct an auxiliary signal, of which the symbol jumping information is abstracted by the wavelet transform. Furthermore, its spectrum analysis can perform the accurate symbol rate estimation. The method needs no prior information so that it is easy for the communication reconnaissance and receiving equipments to implement. And simulation indicates that the proposed method has the correction of 99％ for the symbol rate estimation of OFDM signals modulated by PSK and star-QAM with SNR> 0dB when the estimation error is within 0.1％.

Key words: military electronic countermeasures, orthogonal frequency division multiplexing(OFDM), parameter estimation, wavelet transforms