Title :
On the design of near perfect reconstruction pseudo QMF banks
Author :
Nguyen, Truong Q.
Author_Institution :
Lincoln Lab., MIT, Lexington, MA, USA
Abstract :
A new approach to the design of M-channel pseudo quadrature mirror filter (QMF) banks is presented. The analysis and synthesis filters are cosine-modulated versions of the prototype filters. The prototype filter is constrained to be a linear-phase spectral-factor of a 2Mth band filter. As a result, the reconstructed signal has no amplitude nor phase distortions. The only error at the output is aliasing, which is comparable to the stopband attenuation of the prototype filter. Using this approach, it is possible to design a pseudo-QMF bank where the stopband attenuation of the analysis (and thus synthesis) filters is on the order of 100 dB. Consequently, the resulting reconstruction error is also on the order of -100 dB. An example is included to demonstrate the theory
Keywords :
delay circuits; digital filters; filtering and prediction theory; modulation; network synthesis; 100 dB; M-channel pseudo quadrature mirror filter; analysis filters; cosine-modulated filters; linear-phase spectral-factor; perfect reconstruction pseudo QMF banks; prototype filters; reconstructed signal; reconstruction error; stopband attenuation; synthesis filters; Attenuation; Channel bank filters; Filter bank; Finite impulse response filter; Laboratories; Lattices; Mirrors; Phase distortion; Prototypes; Signal synthesis; Speech coding; Speech synthesis;
Conference_Titel :
Signals, Systems and Computers, 1993. 1993 Conference Record of The Twenty-Seventh Asilomar Conference on
Conference_Location :
Pacific Grove, CA
Print_ISBN :
0-8186-4120-7
DOI :
10.1109/ACSSC.1993.342301
