Improved training sequence structure and timing and frequency synchronization algorithm for OFDM system

• Main Authors: Chen Ying, Nie Wei
• Format: Article
• Language: zho
• Published: National Computer System Engineering Research Institute of China 2019-06-01
• Series: Dianzi Jishu Yingyong
• Subjects: OFDM system; Zadoff-Chu sequence; integer frequency offset; timing synchronization; frequency synchronizatio
• Online Access: http://www.chinaaet.com/article/3000103984

An improved timing and frequency synchronization algorithm based on Zadoff-Chu(ZC) sequence for OFDM system is proposed. The algorithm constructs a training sequence with conjugate repetition relationship. Firstly, the timing synchronization is completed by utilizing the conjugate characteristics of the training sequence in time domain, and the integer frequency offset(IFO) estimation is obtained directly, not affected by the frequency synchronization performance. Then the fractional frequency offset(FFO) estimation is done using the repeatability of the training sequence after timing synchronization. Theoretical analysis and simulation results show that the improved algorithm′s timing and frequency offset estimation mean square error is lower, the integer and fractional frequency offset estimation range is expanded, and computational complexity is reduced.