Type II Polyphase Decomposition
The polyphase decomposition of
into
channels in
(11.11) may be termed a ``type I'' polyphase decomposition. In
the ``type II'', or reverse polyphase decomposition, the powers
of
progress in the opposite direction:
![]() |
(12.14) |
We will see that we need type I for analysis filter banks and type II for synthesis filter banks in a general ``perfect reconstruction filter bank'' analysis/synthesis system.
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N-Channel Polyphase Decomposition