Part 1

Given the Signal 
$ y=cos(pi*t) $

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)

Alumni Liaison

Recent Math PhD now doing a post-doctorate at UC Riverside.

Kuei-Nuan Lin