Channel identification and interference compensation for OFDM system in long multipath environment

Authors:
L. Sun;A. Sano;W. Sun;A. Kajiwara
Affiliations:
Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino, Wakamatsu-ku, Kitakyushu 808-0135, Japan;Department of System Design Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan;Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino, Wakamatsu-ku, Kitakyushu 808-0135, Japan;Faculty of Environmental Engineering, The University of Kitakyushu, 1-1 Hibikino, Wakamatsu-ku, Kitakyushu 808-0135, Japan
Venue:
Signal Processing
Year:
2009

Citing 6
Cited 0

Digital communications

Digital communications
Unification and evaluation of equalization structures and design algorithms for discrete multitone modulation systems

IEEE Transactions on Signal Processing - Part I
Blind, adaptive channel shortening by sum-squared auto-correlation minimization (SAM)

IEEE Transactions on Signal Processing
Echo cancellation in DMT-receivers: circulant decomposition canceler

IEEE Transactions on Signal Processing
Adaptive bit rate maximizing time-domain equalizer design for DMT-based systems

IEEE Transactions on Signal Processing
CINR difference analysis of optimal combining versus maximal ratio combining

IEEE Transactions on Wireless Communications

Quantified Score

Hi-index	0.08

Visualization

Abstract

Guard interval (GI) is usually applied to reduce the influence caused by multipath interferences in orthogonal frequency division multiplexing (OFDM) systems. However, the long multipath interferences will deteriorate the orthogonality of the sub-carriers if they have longer delay time than GI. It is illustrated that not only inter-symbol interference (ISI) but also inter-carrier interference (ICI) is caused by the collapse of orthogonality in the received signal. As a result, both the channel identification and equalization become difficult, and the communication performance cannot be guaranteed. In this work, a new channel identification algorithm is proposed to estimate the frequency response function from the spectral periodograms which are compensated by the replica of leakage error. Since most of the computation is performed in the frequency domain through fast Fourier transform, the algorithm has such low computational complexity that it can be implemented easily in applications.