Revision as of 18:12, 10 September 2008 by Serdbrue (Talk)

Part 1

Given the Signal 
$ y=cos(pi*t) $
One can make 2 DT Signals which are periodic and non periodic.

Lets say the Sampling rate is 1. Then the Signal is non periodic as seen in the diagram below.

Nonper ECE301Fall2008mboutin.jpg

If the sampling frequency is 2 then the Signal is periodic as seen below.

Per ECE301Fall2008mboutin.jpg

MATLAB CODE

t=[1 2 3 4 5 6 7 8 9 10 11 12 13]
y=cos(pi.*t)
figure(1)
plot(t,y,'.')
xlabel('Time')
ylabel('cos(pi*t)')
title('NonPeriodic Signal)')
t=t.*(2)
y=cos(pi.*t)
figure(2)
plot(t,y,'.')
xlabel('Time')
ylabel('cos(pi*t')
title('NonPeriodic Signal)')

Part 2

The non Periodic CT Signal is 2^t
I made this periodic my shift 2^t from 0 to 4 several times as seen in the picture below

Part2 ECE301Fall2008mboutin.JPG

MATLAB CODE

t=0:.001:4;
y=2.^t;
plot(t,y,t+4,y,t+8,y,t+12,y,t+16,y)

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