# Test Signal !!

Started by December 16, 2003
 Hi Everyone.....Well this is Nitin here and I am doing my MS from the University of Hartford. Actually , I wanted to know, suppose I have designed a Butterworth filterusing the "Butter" command in Matlab and "Buttord" for finding the order of the Filter ... Now I got the Frequency response by using the "Freqz" command. Now I want to test the filter using a test signal in the passband frequecy, how should I generate the test signal and then finally analyze the filter....how the Filter behaves with the Test Signal. Thanks Nitin
Hi Nitin!

I sugest random sequence, white Gaussian noise:

x=randn(1024,1);

LP filter is:

L=7;
F=0.2;
[B,A]=butter(L,2*F);

y is filtered signal

y=filter(B,A,x);

Spectrums of original (x) and filtered signal are performed by FFT:

Xt(x);
Xas(X);
Yt(y);
Yas(Y);

Plotting of amplitude spectrums:

plot(Xa);
plot(Ya);
Regards
Predrag Valozic
----- Original Message -----
From: <>
To: <>
Sent: 2003. prosinac 16 13:04
Subject: [matlab] Test Signal !! > Hi Everyone.....Well this is Nitin here and I am doing my MS from the
> University of Hartford.
> Actually , I wanted to know, suppose I have designed a Butterworth
> filterusing the "Butter" command in Matlab and "Buttord" for finding
> the order of the Filter ...
> Now I got the Frequency response by using the "Freqz" command.
> Now I want to test the filter using a test signal in the passband
> frequecy, how should I generate the test signal and then finally
> analyze the filter....how the Filter behaves with the Test Signal.
> Thanks
> Nitin >
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 check out sptool ,fdatool and filter. Mandar --- wrote: > Hi Everyone.....Well this is Nitin here and I am doing my MS from > the > University of Hartford. > Actually , I wanted to know, suppose I have designed a Butterworth > filterusing the "Butter" command in Matlab and "Buttord" for > finding > the order of the Filter ... > Now I got the Frequency response by using the "Freqz" command. > Now I want to test the filter using a test signal in the passband > frequecy, how should I generate the test signal and then finally > analyze the filter....how the Filter behaves with the Test Signal. > Thanks > Nitin > ===== - Its not life that weighs us down, Its how we carry it. __________________________________