Direct Design of Near Perfect Reconstruction Linear Phase Nonuniform Filter Banks with Rational Sampling Factors
A direct method of designing linear phase (LP) near perfect reconstruction (NPR) nonuniform filter banks (NUFBs) with rational sampling factors is presented. Conditions on the possible sampling factors of NUFBs are given. The band position relations and phase relations of the significant aliasing components are also analyzed. Based on these two relations, we derive a necessary condition on the elimination of significant aliasing distortion (ALD). Meanwhile LP property is met. Moreover, a set of relations of the filters are presented to minimize the ALD further. In our proposed method, the LP NUFBs with high stopband attenuation and low system delay can be easily designed without nonlinear optimization procedure