A precise frequency offset estimator for OFDM system

Author

Luo, Xiao ; Yan, Chunlin ; Tang, Youxi ; Li, Shaoqian

Author_Institution

Nat. Key Lab of Commun., Univ. of Electron. Sci. & Technol. of China, Chengdu, China

Volume

7

fYear

2004

fDate

26-29 Sept. 2004

Firstpage

5288

Abstract

In this paper, we proposed a new frequency synchronization method for orthogonal frequency division multiplexing (OFDM) system by using PN sequences. It is an improvement of Tufvesson´s method. In the new method the frequency offset is estimated in two steps. First a small step (span of the correlation) is used for estimation of frequency offset which will result in a larger estimation range but is less precise. After the frequency offset has been compensated, the second estimation is conducted which is a large step. The new algorithm has large estimation range and the estimation is more precise. Performance of the new estimator is improved drastically compared to that of the old one. In AWGN channels, the Cramer-Rao bound of the new method is achieved and it coincides with the Cramer-Rao bound of Schmidl´s method.

Keywords

AWGN channels; OFDM modulation; correlation methods; frequency estimation; synchronisation; AWGN channel; Cramer-Rao bound; OFDM system; PN sequences; correlation span; estimation range; frequency offset compensation; frequency offset estimator; frequency synchronisation method; orthogonal frequency division multiplexing system; AWGN channels; Bandwidth; Fading; Fast Fourier transforms; Frequency division multiplexing; Frequency estimation; Frequency synchronization; Mobile communication; OFDM; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th

ISSN

1090-3038

Print_ISBN

0-7803-8521-7

Type

conf

DOI

10.1109/VETECF.2004.1405111

Filename

1405111