An Improved OFDM Symbol Synchronization Algorithm Based on Cyclic Prefix

• 1、School of Information and Communication Engineering,BUPT
• 2、Communication and Information System, BUPT

Abstract：This paper presents a revised symbol synchronization scheme for OFDM systems that is based on cyclic prefix. Orthogonal frequency division multiplexing (OFDM) has a lot of advantages, such as strong anti-multipath fading, ISI and narrow-band interference abilities, as well as high frequency spectrum utilization, and will become one of the most important broadband wireless communications technologies in future. However, OFDM system is very sensitive to synchronization. Schmidl algorithm is a classic method based on pilot, with advantages of quick capture, high precision, and suitable for emergency communications. But there is a platform in Schmidl curve which impacts on the timing accuracy. Minn improved Schmidl algorithm and had a smooth curve, but it was obtained at the cost of increasing calculations. This algorithm analyzes the reason that results in the platform in Schmidl timing algorithm, and proposed an improved algorithm based on the same training sequence without adding extra complexity. The simulation results show that the performance of timing synchronization gets rid of platform, becomes sharp at the right synchronize time and has a better timing performance.

Keywords： OFDM cyclic prefix multi-path disturbance training sequence