Mitigation of intercarrier interference in OFDM systems over underwater acoustic channels

Transmission schemes based on orthogonal frequency division multiplexing (OFDM) are promising for underwater acoustic (UWA) communications, thanks to their robustness to large multipath spreads. On the other hand, due to the significant time variations in the UWA channels, the effectiveness of the standard OFDM receivers is impaired by intercarrier interference (ICI). In this paper, we propose two novel ICImitigation techniques. In the first scheme, the ICI coefficients are explicitly estimated, and minimum mean square error (MMSE) equalization based on such estimates is performed. In the second approach, no explicit ICI estimation is performed, and detection is based on an adaptive decision-feedback equalizer (DFE) applied in the frequency domain across different subcarriers. We report simulation results showing the effectiveness of the proposed schemes, compared to the performance of a standard OFDM receiver neglecting ICI, and results obtained by processing real data recorded in the recent KAM08 experiment.

[1]  L. Freitag,et al.  Non-Uniform Doppler Compensation for Zero-Padded OFDM over Fast-Varying Underwater Acoustic Channels , 2007, OCEANS 2007 - Europe.

[2]  L. Freitag,et al.  This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination. IEEE JOURNAL OF OCEANIC ENGINEERING 1 Peer-Reviewed Technical Communication Multicarrier Communication Over Un , 2022 .

[3]  Hsiao-Chun Wu,et al.  Robust and Efficient Intercarrier Interference Mitigation for OFDM Systems in Time-Varying Fading Channels , 2007, IEEE Transactions on Vehicular Technology.

[4]  Qing Chang,et al.  Channel Estimation and ICI Cancellation for OFDM Systems in Fast Time-Varying Environments , 2008, IEICE Trans. Commun..

[5]  Paul Hursky,et al.  Multiinput multioutput OFDM for shallow‐water UWA communications , 2008 .

[6]  M. Stojanovic,et al.  Underwater Acoustic Communications: Design Considerations on the Physical Layer , 2008, 2008 Fifth Annual Conference on Wireless on Demand Network Systems and Services.

[7]  J. A. Catipovic,et al.  Phase-coherent digital communications for underwater acoustic channels , 1994 .

[8]  J.A.C. Bingham,et al.  Multicarrier modulation for data transmission: an idea whose time has come , 1990, IEEE Communications Magazine.

[9]  James R. Zeidler,et al.  Techniques for suppression of intercarrier interference in OFDM systems , 2005, IEEE Wireless Communications and Networking Conference, 2005.

[10]  Per Ola Börjesson,et al.  ML estimation of time and frequency offset in OFDM systems , 1997, IEEE Trans. Signal Process..

[11]  Andreas F. Molisch,et al.  Iterative Methods for Cancellation of Intercarrier Interference in OFDM Systems , 2007, IEEE Transactions on Vehicular Technology.