DocumentCode :
1509517
Title :
A new delayless subband adaptive filter structure
Author :
Merched, Ricardo ; Diniz, Paulo S R ; Petraglia, Mariane R.
Author_Institution :
Dept. of Electron. Eng., Fed.. Univ. of Rio de Janeiro, Brazil
Volume :
47
Issue :
6
fYear :
1999
fDate :
6/1/1999 12:00:00 AM
Firstpage :
1580
Lastpage :
1591
Abstract :
Adaptive subband techniques have been developed to reduce complexity and slow convergence problems of the traditional fullband high-order adaptive filters. Some of the disadvantages often encountered in most of the proposed architectures are the effect of aliasing associated with the multirate structure, which is a source of error in the modeling of the unknown system, and the delay introduced in the signal path. We present a new delayless maximally decimated structure where the optimal subband filters are related to the wideband system in a closed form. They make use of a special DFT analysis filterbank where the polyphase components of the prototype filter represent fractional delays so that there is no need for adaptive cross-filters, and the unknown system can modeled perfectly in a closed-loop scheme. We interpret the proposed structure as a special case of a block adaptive filter with lower computational complexity than the conventional fullband LMS algorithm. Some computer simulations are presented in order to verify the good features of the proposed structure
Keywords :
adaptive filters; adaptive signal processing; channel bank filters; computational complexity; convergence of numerical methods; discrete Fourier transforms; filtering theory; DFT analysis filterbank; aliasing; block adaptive filter; closed-loop scheme; complexity reduction; computational complexity; computer simulations; delayless maximally decimated structure; delayless subband adaptive filter structure; error source; fullband high-order adaptive filters; multirate structure; optimal subband filters; polyphase components; slow convergence problems; wideband system; Adaptive filters; Computational complexity; Computer simulation; Convergence; Delay effects; Delay systems; Filter bank; Least squares approximation; Prototypes; Wideband;
fLanguage :
English
Journal_Title :
Signal Processing, IEEE Transactions on
Publisher :
ieee
ISSN :
1053-587X
Type :
jour
DOI :
10.1109/78.765127
Filename :
765127
Link To Document :
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