Part 1

Choose the signal $ x(t)=cos(t) $ which is periodic.

Sampling ever interger yields

This is $ x[n]=cos(n) $

but sampling at a frequency of $ \pi/4 $ yields

This is $ x[n]=cos(\pi/4n) $

Part 2

This is $ x(t)=e^{-t}cos(20t) $ as the nonperiodic signal.


I haven't played around with matlab enough to know how to create the signal needed with my own code, so I used the same code that Ben Laskowski used:


"y=zeros(size(x));

for count=1:period/delta:(nperiod+8)*period/delta

   y(1,count:size(y,2))=y(1,count:size(y,2))+f(1,1:size(y,2)-count+1);

end

plot(x,y)"


Alumni Liaison

To all math majors: "Mathematics is a wonderfully rich subject."

Dr. Paul Garrett