On the relationship between pseudo-QMF designs and perfect-reconstruction solutions for modulated filter banks
Jörg Kliewer · 2003
The classical pseudo-QMF approach for modulated filter banks is related to a previously published general perfect reconstruction (PR) description for integer oversampling ratios. It is shown that a pseudo-QMF prototype approximately satisfies the PR conditions, where the error depends on the remaining linear distortions and on the stopband attenuation of the prototype. For the non-subsampled case the pseudo-QMF and the PR condition are equivalent. Furthermore, an upper bound for the PR-approximation error can be given, when the maximum allowable deviation from the ideal flat frequency response of the analysis-synthesis system is specified.