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simple LPF

Date1999-03-19 10:15
FromSergey Batov
Subjectsimple LPF
Hi,
sorry for "loop" but I'd like to ask it again:
is it possible to know characteristics  (cutoff frequency,
e.t.c.) of the LPF:

a3 delay1 a2
afeedback=(a2+a3)*.5 ?

Thank you,

Date1999-03-19 17:55
FromErik Spjut
SubjectRe: simple LPF
Frequency response is:

     (1 + exp(-j omega))/2

which has a magnitude response of:

     Cos(Pi f/sr)

or 1 at f/sr=0, -3dB at f/sr=0.25, 0 at f/sr=0.5

And a phase response of

     phi in degrees = -180 f/sr

f is frequency, sr is sampling rate. Anything else?

At 1:15 PM +0300 3/19/99, Sergey Batov wrote:
>Hi,
>sorry for "loop" but I'd like to ask it again:
>is it possible to know characteristics  (cutoff frequency,
>e.t.c.) of the LPF:
>
>a3 delay1 a2
>afeedback=(a2+a3)*.5 ?
>
>Thank you,
>Sergey Batov   batov@glasnet.ru


Dr. R. Erik Spjut