OFDM Time Synchronization Method of Underwater Sound Based on Short-time Fourier Transform

摘要

Orthogonal Frequency Division Multiplexing (OFDM) technology has advantages such as anti-multipath, sufficient frequency band utilization and high data transmission rate, so it has significant development prospects for underwater acoustic communication. Inaccurate timing synchronization will result in inter-symbol interference and inter-subcarrier interference in OFDM underwater acoustic communication. Thus, this paper proposes a time synchronization method based on short Fourier transform (STFT) and where timing synchronization is achieved through the pilot signal in the OFDM subcarrier. STFT is conducted for such pilot signal. Then, spectral analysis is carried out. The plane area generated by STFT is used for timing. The simulation and experimental results indicate this is feasible and effective.