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Journal of Applied Sciences >

2013 , Vol. 31 >Issue 2: 142 - 146

DOI: https://doi.org/10.3969/j.issn.0255-8297.2013.02.006

Communication Engineering

Optimization of Time-Frequency Synchronization in OFDM System

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  • 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 date: 2011-09-15

  Revised date: 2012-03-16

  Online published: 2012-03-16

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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

Cite this article

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 . DOI: 10.3969/j.issn.0255-8297.2013.02.006

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