Frequency-domain equalization (FDE) is an effective technique for high data rate wireless communication systems suffering from very long intersymbol interference. Most of existing FDE algorithms are limited to slow time-varying fading channels due to lack of accurate channel estimator. In this paper, we employ interpolation method to propose new algorithms for frequency-domain channel estimation for both slow and fast timevarying fading.We show that least squares-based channel estimation and minimum mean square error-based channel estimation with interpolations are equivalent under certain conditions. Noise variance estimation and channel equalization in the frequency domain are also discussed with fine-tuned formulas. Numerical examples indicate that the new algorithms perform very well for severe fading channels with long delay spread and high Doppler spread. It is also shown that our new algorithms outperform recently developed frequency-domain least mean squares (LMS) and recursive least squares (RLS) algorithms which are capable of dealing with moderate fading channels.


Electrical and Computer Engineering


National Science Foundation (U.S.)
United States. Office of Naval Research

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Article - Journal

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Final Version

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© 2009 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.