Window Based Prototype Filter Design for Highly Oversampled Filter Banks in Audio Applications

Abstract

This paper describes a window based method for designing near perfect-reconstruction prototype filters for highly oversampled, complex modulated filter banks. The design method extends some well-known simple methods for critically sampled filter banks to the over-sampled case and to the case of different length analysis and synthesis filters. This design method is simple and effective for designing a large range of filter bank configurations. The design method is particularly useful in developing audio applications using oversampled filter banks where the target system's requirements are highly variable. The simplicity and flexibility of the design method means that this one method can be used to generate multiple prototype filters as the application requirements change.