# Coefficient calculation of bandpessfilter in SIGMA STUDIO

Started by March 19, 2010
hi everybody..

i have some queries regarding the coefficient calculation of filter in
SIGMA STUDIO software..

in the software they had provided equation to calculate the coefficients

ie:in 2nd order band pass filter design in the calculation of alpha
they didn't provide the closing braces of SINH part
eqation is like this

alpha = sin(w0) * sinh( ln(2)/2 * bandwidth * w0/sin(w0)

w0=2*pi*f0/fs
also the bandwidth provide is bandwidth octaves or bandwidth in hertz
ie bandwithQ

where f0-> center frequency
Q= sqrt(2^N)/((2^N) -1)

N-> bandwidth octaves

with regards
rammya
Howdy Rammya,

http://www.mathworks.com/products/filterdesign/demos.html?file=/products/demos/shipping/filterdesign/parameqdemo.html

About a third of the way down it shows the same formula with all
parenthesies intact.

Patience, persistence, truth,
Dr. mike

On Wed, 17 Mar 2010, r...@ymail.com wrote:

> hi everybody..
>
> i have some queries regarding the coefficient calculation of filter in
> SIGMA STUDIO software..
>
> in the software they had provided equation to calculate the coefficients
>
> ie:in 2nd order band pass filter design in the calculation of alpha
> they didn't provide the closing braces of SINH part
> eqation is like this
>
> alpha = sin(w0) * sinh( ln(2)/2 * bandwidth * w0/sin(w0)
>
> w0=2*pi*f0/fs
> also the bandwidth provide is bandwidth octaves or bandwidth in hertz
> ie bandwithQ
>
> where f0-> center frequency
> Q= sqrt(2^N)/((2^N) -1)
>
> N-> bandwidth octaves
>
> with regards
> rammya
>