On Tue, Dec 8, 2015 at 9:30 AM, R Schumacher <rays@blue-cove.com> wrote:

We have a function which describes a frequency response correction to piezo devices we use. To flatten the FFT, it is similar to:

Cdis_t = .5

N = 8192

for n in range(8192):

B3 = n * 2560 / N

Fc(n) = 1 / ((B3/((1/(Cdis_t*2*pi))**2+B3**2)**0.5)*(-0.01*log(B3) + 1.04145))

In practice it really only matters for low frequencies.

I suggested that we might be able to do a time domain correction as a forward-reverse FFT filter using the function, but another said it can also be applied in the time domain using a bilinear transform.

So, can one use

http://docs.scipy.org/doc/scipy-0.16.0/reference/generated/scipy.signal.bilinear.html

and, how does one generate b,a from the given Fourrier domain flattening function?

Chuck