Aparna Ram wrote:
Dear All,

I am working on the Polyphase IIR filter for subbanding
in Acoustic Echo Cancellation. For subbanding I am using Polyphase IIR
filter.
To calculate the coefficents of Polyphase IIR filter, I
am not getting any sufficient information (for calculation of
coefficients of Polyphase IIR filter) from any documents.
I found some existed Polyphase IIR filter coefficient
values but I want to know that how to calculate the filter
coefficients of Polyphase IIR filter.
In some documents I found that bit-flipping algorithm is
used for the designing(calculatin of coefficients) of Decimated
Polyphase IIR filter. But when I went through the bit-flipping
algorithm I understood that it is used to optimise the calculated(or
existed) coefficients constrained to the coefficient bit length.
So first I have to calculate the coefficients of filter by
some method and then I have to optimise that.
But to calculate that coefficient values I am finding the
related documents.
If any one knows the links and information regarding this
please reply to this mail.
Waiting for your valuable suggestions and replies.

Thanks in advance.

Regards,
Aparna Ram.K.

I know that 2+2=4, is that what you are looking for?