A unifying framework for analysis/Synthesis systems based on maximally decimated filter banks

Abstract

The performance of subband coders relies heavily on the ability of the analysis system to isolate contiguous frequency bands of speech. Typically analysis/synthesis systems introduce aliasing and short-time spectral distortion. A variety of approaches have been introduced in the past that allow some or all of these sources of degradation to be removed. This paper presents a unifying framework which allows these many diverse approaches to be compared and contrasted in terms of the fundamental design issues. In particular, this framework allows the critical issues of aliasing, spectral distortion, efficiency, stability, etc. that are important in a practical system to be specifically addressed. This, in turn, leads to a new understanding of the relationships among many published approaches. But more important, it leads to the definition of many new realizations as well, particularly in the area of exactly-reconstructing analysis/synthesis systems based on maximally decimated filter banks.