An Equalization Technique for High-Speed-Mobile OFDM Systems in Rayleigh Multipath Channels

Dongguo LI  Katsumi YAMASHITA  

Publication
IEICE TRANSACTIONS on Communications   Vol.E87-B   No.1   pp.158-160
Publication Date: 2004/01/01
Online ISSN: 
DOI: 
Print ISSN: 0916-8516
Type of Manuscript: LETTER
Category: Fundamental Theories
Keyword: 
OFDM,  Doppler shift,  Rayleigh fading,  sampling theorem,  Nyquist rate,  

Full Text: PDF(287.5KB)>>
Buy this Article




Summary: 
In mobile OFDM systems, sub-carriers orthogonality will be broken due to Doppler shift, and this results in inter-carrier interference (ICI). Many methods have been proposed to compensate for this, however, these methods won't be suitable for fast fading caused by high mobile speed. In this letter, we propose a novel sampling theorem based pilot symbol-aided technique which can not only estimate the channel fading envelope (CFE) accurately under high relative Doppler frequency (RDF) but also achieve lower BER than conventional methods. The validity of the proposed method is demonstrated by computer simulations.