OFDM系统的时频同步优化

doi:10.3969/j.issn.0255-8297.2013.02.006

Journal of Applied Sciences ›› 2013, Vol. 31 ›› Issue (2): 142-146.doi: 10.3969/j.issn.0255-8297.2013.02.006

• Communication Engineering • Previous Articles Next Articles

Optimization of Time-Frequency Synchronization in OFDM System

ZHAO Jun-hui1,2, LÜ Chen1, TAN Guo-ping3

1. State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University, Beijing 100044, China
2. School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing 100044, China
3. College of Computer and Information Engineering, Hohai University, Nanjing 211100, China

Received:2011-09-15 Revised:2012-03-16 Online:2013-03-25 Published:2012-03-16

Abstract

Abstract: This paper studies joint synchronization in OFDM systems under multipath fading, and analyzes the reason of timing error in the existing algorithms. An optimized joint synchronization algorithm using PN sequence is proposed. The algorithm achieves time synchronization by looking for the first falling edge
of the sliding correlation sum value, chooses a size of the search window for the correlation sum value. Modified correlation calculation is introduced in the frequency synchronization. Simulation results show stability and superiority of the new algorithm under multipath environment, especially when the first path is not the strongest.

Key words: orthogonal frequency division multiplexing, timing synchronization, frequency synchronization, multipath fading channels

CLC Number:

TN929.5

ZHAO Jun-hui1,2, Lü Chen1, TAN Guo-ping3. Optimization of Time-Frequency Synchronization in OFDM System[J]. Journal of Applied Sciences, 2013, 31(2): 142-146.

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Optimization of Time-Frequency Synchronization in OFDM System

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