Oversampled filter bank evaluation for joint subband audio processing and coding

This paper presents an experimental evaluation of oversampled, modulated filter banks for joint subband audio processing and coding applications. Joint subband processing and coding may be useful in some wireless audio devices such as advanced wireless digital hearing aids. We examine the use of oversampled GDFT and cosine modulated filter banks and propose using single sideband (SSB) real-valued filter banks as a compromise which is ideal for this application. The SSB filter bank provides real-valued signals for audio coding which are free from any aliasing cancellation constraints and hence are also suitable for audio processing such as subband gain adjustment. We support this conclusion with an experimental analysis of various filter bank designs for subband gain adjustment and subband audio coding.