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Journal of Applied Sciences >

2012 , Vol. 30 >Issue 6: 573 - 580

DOI: https://doi.org/10.3969/j.issn.0255-8297.2012.06.003

Communication Engineering

Decision Directed Channel Equalization for OFDM Underwater Acoustic Communications

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  • 1. National Laboratory of Underwater Acoustic Technology, Harbin Engineering University, Harbin 150001, China 
    2. College of Information and Communication Engineering, Harbin Engineering University,Harbin 150001, China

Received date: 2010-10-20

  Revised date: 2011-08-10

  Online published: 2011-08-10

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Abstract

Complication of ocean channels causes sub-carrier amplitude fading and phase distortion in underwater communication. To reduce the effects of channel estimation error due to time variation and interpolation error, a decision-directed channel equalization algorithm for OFDM-based communication is proposed. Error control codes are used for decision making so that the data decisions can be used as pilots, with which channel estimation is performed. Taking into account different environment conditions, equalization is done using a decision-directed scheme with block piloting and a decision twice-equalization scheme with comb piloting. Results of simulation and lake experiments are promising, showing that the proposed scheme can effectively
improve system performance without loss of bandwidth efficiency.

Key words： underwater acoustic communication; orthogonal frequency division multiplexing (OFDM); channel equalization; decision equalization

Cite this article

MA Xue-fei1, QIAO Gang1, ZHAO Chun-hui2, MA Lu1 . Decision Directed Channel Equalization for OFDM Underwater Acoustic Communications[J]. Journal of Applied Sciences, 2012 , 30(6) : 573 -580 . DOI: 10.3969/j.issn.0255-8297.2012.06.003

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