Title
Factorization approach to unitary time-varying filter bank trees and wavelets
Abstract
A complete factorization of all optimal (in terms of quick transition) time-varying FIR unitary filter bank tree topologies is obtained. This has applications in adaptive subband coding, tiling of the time-frequency plane and the construction of orthonormal wavelet and wavelet packet bases for the half-line and interval. For an M-channel filter bank the factorization allows one to construct entry/exit filters that allow the filter bank to be used on finite signals without distortion at the boundaries. One of the advantages of the approach is that an efficient implementation algorithm comes with the factorization. The factorization can be used to generate filter bank tree-structures where the tree topology changes over time. Explicit formulas for the transition filters are obtained for arbitrary tree transitions. The results hold for tree structures where filter banks with any number of channels or filters of any length are used. Time-varying wavelet and wavelet packet bases are also constructed using these filter bank structures. the present construction of wavelets is unique in several ways: 1) the number of entry/exit functions is equal to the number of entry/exit filters of the corresponding filter bank; 2) these functions are defined as linear combinations of the scaling functions-other methods involve infinite product constructions; 3) the functions are trivially as regular as the wavelet bases from which they are constructed
Year
DOI
Venue
1995
10.1109/78.370621
IEEE Transactions on Signal Processing
Keywords
Field
DocType
FIR filters,digital filters,matrix decomposition,signal reconstruction,time-varying filters,trees (mathematics),wavelet transforms,FIR unitary filter bank tree topologies,M-channel filter bank,adaptive subband coding,efficient implementation algorithm,entry/exit filters,factorization,finite signals,infinite product constructions,linear combinations,orthonormal wavelet,perfect reconstruction filters,scaling functions,tiling,time-frequency plane,transition filters,tree topology,unitary time-varying filter bank trees,wavelet packet bases
Mathematical optimization,Quadrature mirror filter,Digital filter,Filter bank,Adaptive filter,Wavelet packet decomposition,Mathematics,Wavelet,Wavelet transform,Filter design
Journal
Volume
Issue
ISSN
43
3
1053-587X
Citations 
PageRank 
References 
10
1.11
12
Authors
2
Name
Order
Citations
PageRank
R. A. Gopinath141748.03
C. S. Burrus239175.14