Semiblind Iterative Data Detection for OFDM Systems with CFO and Doubly Selective Channels

Author

He, Lanlan ; Ma, Shaodan ; Wu, Yik-Chung ; Ng, Tung-Sang

Author_Institution

Dept. of Electr. & Electron. Eng., Univ. of Hong Kong, Hong Kong, China

Volume

58

Issue

12

fYear

2010

fDate

12/1/2010 12:00:00 AM

Firstpage

3491

Lastpage

3499

Abstract

Data detection for OFDM systems over unknown doubly selective channels (DSCs) and carrier frequency offset (CFO) is investigated. A semiblind iterative detection algorithm is developed based on the expectation-maximization (EM) algorithm. It iteratively estimates the CFO, channel and recovers the unknown data using only limited number of pilot subcarriers in one OFDM symbol. In addition, efficient initial CFO and channel estimates are also derived based on approximated maximum likelihood (ML) and minimum mean square error (MMSE) criteria respectively. Simulation results show that the proposed data detection algorithm converges in a few iterations and moreover, its performance is close to the ideal case with perfect CFO and channel state information.

Keywords

OFDM modulation; expectation-maximisation algorithm; least mean squares methods; MMSE; OFDM systems; approximated maximum likelihood criteria; carrier frequency offset; channel state information; doubly selective channels; expectation-maximization algorithm; minimum mean square error criteria; pilot subcarriers; semiblind iterative data detection; Channel estimation; Correlation; Covariance matrix; Detection algorithms; Matrix decomposition; OFDM; Receivers; Carrier frequency offset (CFO); data detection; doubly selective channel (DSC); expectation-maximization (EM); orthogonal frequency division multiplexing (OFDM);

fLanguage

English

Journal_Title

Communications, IEEE Transactions on

Publisher

ieee

ISSN

0090-6778

Type

jour

DOI

10.1109/TCOMM.2010.092810.090682

Filename

5595116