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===Aliasing===

Aliasing is when different continuous signals become indistinguishable when sampled, this might happen when sampling too slow. It can also refer to the distortion that occurs when a signals are sampled and reconstructed as aliases of the original signals.

Here is an example of aliasing:

[[Image:Signals 2hw-11.jpg]]
[[Image:Signals hw-11.jpg]]

Like we can see in this images, the samples that we are getting out of the yellow wave, can be also samples in the blue one.


Script for Matlab:
clear all;

t=0:.01:1;

T=0.20;

ts=0:T:1;

f1=2;

f2=1/0.125;

plot(t,cos(2*pi*f2*t),'b-',ts,cos(2*pi*f1*ts),'r*',t,cos(2*pi*f1*t),'y-');

plot(ts,cos(2*pi*f1*ts),'r*',t,cos(2*pi*f1*t),'y-');