Research of Time-Frequency Synchronization Technology Based on OFDM System

In the high-speed motion scenario, large Doppler shift causes large carrier frequency offset. Carrier frequency offset has great influence on the traditional timing synchronization algorithm, which cannot get the exact symbol starting position. In addition, the traditional integer frequency offset estimation algorithm has strict requirements on timing synchronization, and a slight deviation will fail to estimate correctly. Therefore, a multi-module time-frequency synchronization algorithm is designed in this paper. The sensitivity of timing synchronization algorithm to large frequency deviation and integer frequency doubling deviation estimation algorithm to synchronization error is eliminated by using twice difference operation. Through MATLAB simulation in different channel environments, it is shown that the time-frequency synchronization scheme implemented in this paper has good synchronization performance under multipath Doppler channel.