(Broken MATLAB code)
 
Line 14: Line 14:
  
 
[[Image:Jkubasci Fixed plot_ECE301Fall2008mboutin.png]]
 
[[Image:Jkubasci Fixed plot_ECE301Fall2008mboutin.png]]
 +
 +
This looks correct.  Thus, the problem was not with the code, but with the sampling period chosen.  The value <math>T_{s}=0.07</math> roughly sampled one point from each period of the sinusodial wave, which was not fine enough to describe the wave sufficiently.

Latest revision as of 17:53, 11 September 2008

After running the given MATLAB code, the following plot was produced:

Orig plot ECE301Fall2008mboutin.png

As seen above, the picture does not resemble a 13Hz sinusoidal wave repeated 13 times. The function that was suppose to be plotted by the code should be

$ \,x(t)=Re[e^{j(2\pi F_{o}t-\frac{pi}{2})}]\, $

$ \,x(t)=Re[cos(2\pi F_{o}t-\frac{pi}{2})+jsin(2\pi F_{o}t-\frac{pi}{2})]\, $

$ \,x(t)=cos(2\pi F_{o}t-\frac{pi}{2})\, $

which appears to be correct. However, the sampling period $ T_{s}=0.07 $ only provides 14 points on the graph, which appears to be not enough. If we increase the number of sampling points by a factor of 10 (with a new value $ T_{s}=0.007 $), the following plot is produced:

Jkubasci Fixed plot ECE301Fall2008mboutin.png

This looks correct. Thus, the problem was not with the code, but with the sampling period chosen. The value $ T_{s}=0.07 $ roughly sampled one point from each period of the sinusodial wave, which was not fine enough to describe the wave sufficiently.

Alumni Liaison

Have a piece of advice for Purdue students? Share it through Rhea!

Alumni Liaison