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Title: Improved BDFE using a priori information for turbo equalization
Author (s): Wu, Jingxian
Leong, Sang-Yick
Lee, Kah-Ping
Xiao, Chengshan
Olivier, Jan C.
Department/Lab Affiliations: Electrical and Computer Engineering
Keywords: block decision feedback equalization
iterative equalization
sequence detection
turbo equalization
Issue Date: 2008-01
Publisher: Institute of Electrical and Electronics Engineers IEEE
Citation: Wu, J., Leong, S.Y., Lee, K.P., Xiao, C., and Olivier, J.C. “Improved BDFE using a priori information for turbo equalization.” IEEE Transactions Wireless Communications, vol. 7, no. 1, pp. 233-240, 2008.
Abstract: Turbo equalization improves communication system performance by iteratively exchanging information between soft-input soft-output (SISO) equalizer and SISO channel decoder. The trellis-based maximum a posteriori probability (MAP) algorithm serves as the optimum SISO equalizer for turbo equalization. However, MAP algorithm is unsuitable for systems with large modulation constellation size and severe inter-symbol interference (ISI) due to its prohibitively high computational complexity. In this paper, an improved SISO block decision feedback equalizer (BDFE) is proposed for low complexity turbo equalization. Unlike other sub-optimum equalizers which perform symbol by symbol detection, the proposed equalizer generates the soft output for each data bit by collecting information from a sequence of samples as in MAP algorithm. The sequence-based equalization is enabled by using not only soft a priori input from channel decoder, but also hard a priori information obtained from BDFE in previous iteration. The combination of soft a priori information and hard a priori information renders better performance with less iterations compared to other sub-optimum algorithms. In addition, the computational complexity of the proposed algorithm is on the same order as conventional SISO BDFE algorithm, and is much lower compared to the trellis-based MAP algorithm.
Type: Article - Journal
text
In Title: IEEE Transactions on Wireless Communications
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Publisher URL:
http://dx.doi.org/10.1109/TWC.2008.060463
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titleImproved BDFE using a priori information for turbo equalization
contributor.authorWu, Jingxian
contributor.authorLeong, Sang-Yick
contributor.authorLee, Kah-Ping
contributor.authorXiao, Chengshan
contributor.authorOlivier, Jan C.
contributor.deptlabElectrical and Computer Engineering
contributor.sponsorNational Science Foundation
contributor.sponsorOffice of Naval Research
subjectblock decision feedback equalization
subjectiterative equalization
subjectsequence detection
subjectturbo equalization
date.issued2008-01
publisherInstitute of Electrical and Electronics Engineers IEEE
identifier.citationWu, J., Leong, S.Y., Lee, K.P., Xiao, C., and Olivier, J.C. “Improved BDFE using a priori information for turbo equalization.” IEEE Transactions Wireless Communications, vol. 7, no. 1, pp. 233-240, 2008.
identifier.pub.URI
http://dx.doi.org/10.1109/TWC.2008.060463
description.abstractTurbo equalization improves communication system performance by iteratively exchanging information between soft-input soft-output (SISO) equalizer and SISO channel decoder. The trellis-based maximum a posteriori probability (MAP) algorithm serves as the optimum SISO equalizer for turbo equalization. However, MAP algorithm is unsuitable for systems with large modulation constellation size and severe inter-symbol interference (ISI) due to its prohibitively high computational complexity. In this paper, an improved SISO block decision feedback equalizer (BDFE) is proposed for low complexity turbo equalization. Unlike other sub-optimum equalizers which perform symbol by symbol detection, the proposed equalizer generates the soft output for each data bit by collecting information from a sequence of samples as in MAP algorithm. The sequence-based equalization is enabled by using not only soft a priori input from channel decoder, but also hard a priori information obtained from BDFE in previous iteration. The combination of soft a priori information and hard a priori information renders better performance with less iterations compared to other sub-optimum algorithms. In addition, the computational complexity of the proposed algorithm is on the same order as conventional SISO BDFE algorithm, and is much lower compared to the trellis-based MAP algorithm.
typeArticle - Journal
type.DCMITypetext
type.statusFinal version
rightsThis material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
rightsallows publisher's final version to be uploaded
rights.URI
http://www.ieee.org/web/publications/rights/policies.html
rights.URI
http://www.ieee.org/portal/cms_docs_iportals/iportals/publications/rights/downloads/IEEECForm121302pdf.pdf
rights.URI
http://www.ieee.org/web/publications/rights/index.html
relation.isPartOfIEEE Transactions on Wireless Communications
date.accessioned2008-07-23T18:40:04Z
date.available2008-07-31T20:44:03Z
identifier.persist.URI
http://scholarsmine.mst.edu/post_prints/ImprovedBDFEUsingAPrioriInformationForTurboEq_09007dcc8053e276.html
Full Text
ImprovedBDFE_09007dcc8053e3e8.pdf