[sci.electronics] FIR filters

charlie@oakhill.UUCP (Charlie Thompson) (10/28/87)

This is a question for DSP jocks on the net......


I am designing a really sharp FIR filter for digital audio.
The purpose of the filter is to prevent aliasing for a sample rate
of 44.1 KHz.  For 16 bits I need to be -96 dB at 22.05 KHz.  I would
like the passband to be 20.0 KHz.  My question is this....

Which FIR design technique should work best???

   a) Kaiser Window and Remez Exchange Algorithm

   b) Equi-ripple iterative approach.

Dropping 96 dB in only 10% of the bandwidth is a REALLY sharp filter!
It would also be nice to have less than .01 dB of passband ripple.
I have a hunch as to which one works the best but I'd like to hear
some opinions from someone else.

Thanks.

Charlie Thompson
Austin,TX

hildum@iris.UUCP (10/28/87)

Hello.

You might want to check out the Signetics SAA7030, which is designed
for filtering the output of a CD system.  This chip uses a 4x
resampling system to allow a much cheaper (lower order) filter.

				Eric Hildum