Forums

Scaling to prevent overflow (Fixed Point)

Started by Heureka November 19, 2003
Hi,

I've designed a fixed point filterbank based on cascaded second order
sections. To this stage I have the filter coefficients, but finding it
hard to decide at which nodes the scaling should be done.

Do any of you have some useful design rules?

Some well-written litterature would be great too!

Thomas:)
In article <e2415542.0311190609.1f0b88b2@posting.google.com>,
 stoltzo@hotmail.com (Heureka) wrote:

> Hi, > > I've designed a fixed point filterbank based on cascaded second order > sections. To this stage I have the filter coefficients, but finding it > hard to decide at which nodes the scaling should be done. > > Do any of you have some useful design rules? > > Some well-written litterature would be great too! > > Thomas:)
Download... <http://personal.atl.bellsouth.net/y/a/yatesc/fp.pdf> and <http://personal.atl.bellsouth.net/y/a/yatesc/fir.pdf> -- Remove _me_ for e-mail address
Thanks a lot for your help!

Thomas

"Heureka" <stoltzo@hotmail.com> wrote in message
news:e2415542.0311190609.1f0b88b2@posting.google.com...
> Hi, > > I've designed a fixed point filterbank based on cascaded second order > sections. To this stage I have the filter coefficients, but finding it > hard to decide at which nodes the scaling should be done. > > Do any of you have some useful design rules? > > Some well-written litterature would be great too! > > Thomas:)
Ken Prager wrote:
> In article <e2415542.0311190609.1f0b88b2@posting.google.com>, > stoltzo@hotmail.com (Heureka) wrote: > > >>Hi, >> >>I've designed a fixed point filterbank based on cascaded second order >>sections. To this stage I have the filter coefficients, but finding it >>hard to decide at which nodes the scaling should be done. >> >>Do any of you have some useful design rules? >> >>Some well-written litterature would be great too! >> >>Thomas:) > > > > > Download... > > <http://personal.atl.bellsouth.net/y/a/yatesc/fp.pdf> > > and > > <http://personal.atl.bellsouth.net/y/a/yatesc/fir.pdf> >
It's amazing these still work - I switched to Earthlink about 6 months ago!! Try http://home.earthlink.net/~yatescr/fp.pdf and fir.pdf -- % Randy Yates % "...the answer lies within your soul %% Fuquay-Varina, NC % 'cause no one knows which side %%% 919-577-9882 % the coin will fall." %%%% <yates@ieee.org> % 'Big Wheels', *Out of the Blue*, ELO http://home.earthlink.net/~yatescr