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Carrier Frequency Offset Estimation and I/Q Imbalance Compensation for OFDM Systems

EURASIP Journal on Advances in Signal Processing volume 2007, Article number: 045364 (2007) Cite this article

Abstract

Two types of radio-frequency front-end imperfections, that is, carrier frequency offset and the inphase/quadrature (I/Q) imbalance are considered for orthogonal frequency division multiplexing (OFDM) communication systems. A preamble-assisted carrier frequency estimator is proposed along with an I/Q imbalance compensation scheme. The new frequency estimator reveals the relationship between the inphase and the quadrature components of the received preamble and extracts the frequency offset from the phase shift caused by the frequency offset and the cross-talk interference due to the I/Q imbalance. The proposed frequency estimation algorithm is fast, efficient, and robust to I/Q imbalance. An I/Q imbalance estimation/compensation algorithm is also presented by solving a least-square problem formulated using the same preamble as employed for the frequency offset estimation. The computational complexity of the I/Q estimation scheme is further reduced by using part of the short symbols with a little sacrifice in the estimation accuracy. Computer simulation and comparison with some of the existing algorithms are conducted, showing the effectiveness of the proposed method.

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Authors and Affiliations

  1. Centre for Signal Processing and Communications, Department of Electrical and Computer Engineering, Concordia University, Montreal, Quebec, H3G 1M8, Canada

    Feng Yan, Wei-Ping Zhu & M Omair Ahmad

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  1. Feng Yan
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  2. Wei-Ping Zhu
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  3. M Omair Ahmad
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Correspondence to Feng Yan.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Yan, F., Zhu, WP. & Ahmad, M.O. Carrier Frequency Offset Estimation and I/Q Imbalance Compensation for OFDM Systems. EURASIP J. Adv. Signal Process. 2007, 045364 (2007). https://doi.org/10.1155/2007/45364

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