DocumentCode :
1424450
Title :
Timing recovery for OFDM transmission
Author :
Yang, Baoguo ; Letaief, Khaled ; Cheng, Roger S. ; Cao, Zhigang
Author_Institution :
Dept. of Electron. Eng., Tsinghua Univ., Beijing, China
Volume :
18
Issue :
11
fYear :
2000
Firstpage :
2278
Lastpage :
2291
Abstract :
Orthogonal frequency division multiplexing (OFDM) is an effective modulation technique for high-rate and high-speed transmission over frequency selective fading channels. However, OFDM systems can be extremely sensitive and vulnerable to synchronization errors. In this paper, we present a scheme for performing timing recovery that includes symbol synchronization and sampling clock synchronization in OFDM systems. The scheme is based on pilot subcarriers. In the scheme, we use a path time delay estimation method to improve the accuracy of the correlation-based symbol synchronization methods, and use a delay-locked loop (DLL) to do the sampling clock synchronization. It is shown that by using this scheme, the mean square values of the symbol timing estimation error can be decreased by several orders of magnitude compared to the common correlation methods in both the AWGN and multipath fading channels. In addition, the scheme can track the symbol timing drift caused by the sampling clock frequency offsets.
Keywords :
AWGN channels; OFDM modulation; correlation methods; fading channels; land mobile radio; mean square error methods; multipath channels; personal communication networks; synchronisation; AWGN channels; OFDM transmission; correlation-based symbol synchronization methods; delay-locked loop; effective modulation technique; frequency selective fading channels; high-rate transmission; high-speed transmission; multipath fading channels; orthogonal frequency division multiplexing; path time delay estimation method; pilot subcarriers; sampling clock frequency offsets; sampling clock synchronization; symbol synchronization; symbol timing drift; symbol timing estimation error; synchronization errors; timing recovery; wireless communication systems; Clocks; Correlation; Delay effects; Delay estimation; Estimation error; Fading; Frequency synchronization; OFDM modulation; Sampling methods; Timing;
fLanguage :
English
Journal_Title :
Selected Areas in Communications, IEEE Journal on
Publisher :
ieee
ISSN :
0733-8716
Type :
jour
DOI :
10.1109/49.895033
Filename :
895033
Link To Document :
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