Abstract: Aiming at the problems of the existing Orthogonal Frequency Division Multiplexing (OFDM) frequency offset estimation algorithms, which have a small estimation range and low estimation accuracy, a new training sequence frequency synchronization algorithm is proposed. Firstly, the training sequence and periodic transmission sequence are shortened to increase the range of frequency offset estimation. However, the increase of the frequency offset range will result in a loss of performance. Then, a method is proposed by averaging the estimated values of the short-period repetitive patterns. The performance of the frequency offset estimation is further improved while the estimation range is maintained. Finally, simulation results show that the improved algorithm has a large frequency offset estimation range and high estimation accuracy, and the Mean Square Error (MSE) can reach 10⁻⁶.