A Method for Alias Reduction in Cascaded Filter Banks

This paper shows a new way to reduce aliasing in cascaded filter bank structure. Unlike standard tree structured methods, which lead to many aliasing components in the final subbands, our approach reduces the effect by canceling aliasing elements among subbands. Our interest lies in compression applications where we can apply the scheme to obtain an unequal or non-uniform band splitting using uniform cosine modulated filter banks. In an example it is shown that a reduction in aliasing of over 40 dB compared to a traditional tree structured filter bank can be achieved.