Blind Frequency Offset Correction Algorithm for DWMT System

Yang CAO
Qiang TU
Xiuming SHAN
Yong REN

IEICE TRANSACTIONS on Communications   Vol.E87-B    No.12    pp.3695-3701
Publication Date: 2004/12/01
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Wireless Communication Technologies
DWMT,  OFDM,  sub-carrier frequency offset,  blind estimation,  

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Discrete Wavelet Multi-carrier Transceiver (DWMT) system, which can be viewed as a kind of OFDM, has many advantages because it uses wavelets as its base functions. In this paper we present a new sub-carrier frequency offset correction method for DWMT systems with little assistant information. The essential ideal of this algorithm is: when an orthogonal multi-carrier system is of perfect frequency synchronize, the demodulated signals of different sub-carriers are independent of each other. Whereas when frequency offset exists, intercarrier interference will distort the demodulated signal, i.e. every demodulated signal is the sum of several modulated signals' projects on the demodulating frequency. So the adjacent demodulated signals consist of the element of the same modulated signal, and these demodulated signals are correlated with each other. The degree that they correlated with each other depends on sub-carrier relative frequency offset. Since that little assistant information is used in this algorithm the spectrum efficiency can be largely increased. Simulation results shown that if the number of the sub-carrier of the DWMT system is bigger than 1000, the relative frequency offset can be limited in 2%.