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Adaptive Decision Feedback Equalizer using the hierarchical Feedback filter and Soft decision device  

Lim, Dong-Guk (In-ha University)
Song, Jeong-Ig (In-ha University)
Kim, Jae-Mong (In-ha University)
Publication Information
Journal of the Institute of Electronics Engineers of Korea TC / v.44, no.1, 2007 , pp. 138-145 More about this Journal
Abstract
Wireless transmission system using the multipath channel is affected ISI due to the delay spread. So we use a decision feedback equalizer which consist of decision part and feedback filter for remove the ISI effectively. In this paper, we propose a improved adaptive decision feedback equalizer to mitigate ISI effectively. The proposed adaptive decision feedback equalizer is construct by using soft decision device and hierarchical feedback filter based on MMSE sub-optimal equalizer using the LMS algorithm. Soft decision device mitigate the error propagation in feedback filter by incorrectly detected decision symbol and feedback filter which is divided two step independently mitigate the ISI by using a adaptive algorithm. As a result this structure shows better performance than conventional decision feedback equalizer by mitigating the error propagation in filter cause incorrectly detecting symbol. and we get the MSE more rapidly by using larger step-size due to reduce the number of feedback filter tap. In computer simulation, we compare the bit error rate performance of proposed decision feedback equalizer with conventional one on the S-V channel model for UWB system.
Keywords
equalization; LMS algorithm; Decision Feedback Equalizer; Hierarchical;
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Times Cited By KSCI : 1  (Citation Analysis)
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