Wenwu Xie
Department of Electronic and Information Engineering, Central China Normal University, Wuhan, 430079, China
Shouyin Liu
Department of Electronic and Information Engineering, Central China Normal University, Wuhan, 430079, China
ABSTRACT
In this study, for a multiuser multi-code CDMA system under multipath fading channel, a new Iterative Block Decision-feedback Equalizer (IB-DFE) is proposed, in which the correlation between users is took into consideration. The dispersive channel will weaken the orthogonal between users which induces the following worse effect that the pre-cursor and/or post-cursor Inter-symbol Interference (ISI) from each user will leak to the present symbol. These previous papers, related the multi-user detection with the DFE method, only consider themselves feed-back signal without the other users feed-back signals. Since these feed-back signals of other users have also effect on the desired user, the correlation factor between users will improve the performance compared with the conventional DFE. Generally, the DFE co-exists with the MMSE but the MMSE is biased estimation. In order to keep feedback signal the same scaling with the received signal, the output of the MMSE-DFE must be un-biased. Therefore, the un-biased MMSE-DFE is also considered in this study. Furthermore, the IB-DFE has less complexity compared with the conventional DFE, so this study also extends the IB-DFE with single user to multi-user. The simulation results show that the proposed IB-DFE method, based on correlation between users, outperforms more than 2dB compared with the conventional IB-DFE on a wireless dispersive fading channel.
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How to cite this article
Wenwu Xie and Shouyin Liu, 2013. A New Joint Multiuser Iterative Decision-feedback Equalizer in the Frequency
Domain. Information Technology Journal, 12: 7641-7645.
DOI: 10.3923/itj.2013.7641.7645
URL: https://scialert.net/abstract/?doi=itj.2013.7641.7645
DOI: 10.3923/itj.2013.7641.7645
URL: https://scialert.net/abstract/?doi=itj.2013.7641.7645
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