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I choose y(t)=cos(t) as my continous signal.
 
I choose y(t)=cos(t) as my continous signal.
 
There is no doubt that y(t)=cos(t) is periodic because cos(t + T) = cos(t) where its fundamental period is 2*π
 
There is no doubt that y(t)=cos(t) is periodic because cos(t + T) = cos(t) where its fundamental period is 2*π
First I sample the signal y(t)=cos(t) at 1000 Hz and so we get the following discrete signal which is periodic
 
  
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----
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== Periodic Function ==
 +
 +
 +
First I sample the signal y(t)=cos(t) at  100 Hz and so we get the following discrete signal which is periodic
 +
the matlab code is as follows
 +
<pre>
 +
t=[0:0.01:10]
 +
y=cos(2*pi*t);
 +
stem(t,y); xlabel('sec');
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</pre>
  
---- 
 
 
[[Image:periodic_goklani_ECE301Fall2008mboutin.jpg]]
 
[[Image:periodic_goklani_ECE301Fall2008mboutin.jpg]]
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 +
 +
----
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 +
== Non periodic funtion ==
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 +
 +
 +
* Now if I sample the signal y(t)=cos(t) at 22.22 Hz then we get the following discrete signal which is not periodic
 +
the matlab code is as follows
 +
<pre>
 +
t=[0:0.045:10]
 +
y=cos(2*pi*t);
 +
stem(t,y); xlabel('sec');
 +
</pre>
 +
 +
 +
 +
[[Image:non periodic_goklani_ECE301Fall2008mboutin.jpg]]
 +
 +
 +
----
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 +
== Recurring non periodic function = periodic ==
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 +
Now let us shift the non periodic function y(t)= <math>{e^{3t}}</math>
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 +
 +
we use the following matlab code
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%referred the code of paul sceffler
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<pre>
 +
clc
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clear
 +
 +
t=0.01:.01:1;
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x=exp(3*t);
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i=[];
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for d=1:10
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    i=[i,x];
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end
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 +
t=[0.01:.01:10];
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plot(t,i)
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</pre>
 +
 +
 +
 +
----
 +
[[Image:recurring non periodic_goklani_ECE301Fall2008mboutin.jpg]]
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 +
we see above that the non-periodic signal is now periodic

Latest revision as of 20:44, 11 September 2008

I choose y(t)=cos(t) as my continous signal. There is no doubt that y(t)=cos(t) is periodic because cos(t + T) = cos(t) where its fundamental period is 2*π


Periodic Function

First I sample the signal y(t)=cos(t) at 100 Hz and so we get the following discrete signal which is periodic the matlab code is as follows

t=[0:0.01:10]
y=cos(2*pi*t);
stem(t,y); xlabel('sec');

Periodic goklani ECE301Fall2008mboutin.jpg



Non periodic funtion

  • Now if I sample the signal y(t)=cos(t) at 22.22 Hz then we get the following discrete signal which is not periodic

the matlab code is as follows

t=[0:0.045:10]
y=cos(2*pi*t);
stem(t,y); xlabel('sec');


Non periodic goklani ECE301Fall2008mboutin.jpg



Recurring non periodic function = periodic

Now let us shift the non periodic function y(t)= $ {e^{3t}} $


we use the following matlab code %referred the code of paul sceffler

clc
clear

t=0.01:.01:1;
x=exp(3*t);
i=[];
for d=1:10
    i=[i,x];
end

t=[0.01:.01:10];
plot(t,i)



Recurring non periodic goklani ECE301Fall2008mboutin.jpg

we see above that the non-periodic signal is now periodic

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