The 5G physical layer transmits information in frames. The accuracy of the frame synchronization point will greatly affect the performance of subsequent channels. Aiming at the problem that the current synchronization algorithm detects inaccurate synchronization points

this article analyzes the third-order correlation characteristic of the Primary Synchronization Signal（PSS） sequence

and proposes a new timing synchronization algorithm based on this characteristic. Simulation results show that when the signal-to-noise ratio drops to-7 dB

the accuracy of the proposed algorithm for detecting synchronization points is improved by 20% compared with the traditional algorithm. The space complexity of the new algorithm is consistent with the traditional algorithm

and the increase in time complexity is also within the allowable range of the 5G synchronization process.