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beginer question

Started by Marcin August 5, 2003
How may I determine cutoff frequency of FIR filter?
Thanks
Marcin


"Marcin" <faza0123@interia.pl> wrote in message
news:bgoq36$6gh$1@inews.gazeta.pl...
> How may I determine cutoff frequency of FIR filter? > Thanks > Marcin > >
y=FFT of the array of the FIR coefficients z=absolute value of y Examine y. or, if you want to have a smoother function to look at: y=FFT of the array of the FIR coefficients with a large number of zeros first appended to the array of coefficients. z=absolute value of y Examine y. Fred

Marcin wrote:

> How may I determine cutoff frequency of FIR filter? > Thanks > Marcin
Put a sine wave in and measure when the output goes down 3dB (0.707). Tom