Part A: Periodic Signals Revisited

Periodic Continuous Time Signal

I used the continuous time signal $ x(t) = cos(t) $, as it seemed many people used in Homework 1 for their example of a periodic function. The signal repeats itself at intervals of $ 2\pi $.

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Non-Periodic Discrete Time Signal

Using the CT signal $ x(t) = cos(t) $ and converting it to the DT signal $ x[n] = cos[n] $ will create a non-periodic function when n is sampled at every integer.

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Periodic Discrete Time Signal

In order to create a discrete time signal $ x[n] = cos[n] $ that was still periodic, the time interval couldn't be integers, as shown previously. Therefore, a time interval of $ \pi/2 $ was selected.

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Creating a Periodic from a Non-Periodic Function

Using $ x(t) = \frac{sin(t)}{t} $, which is a non-periodic function, we can create a periodic function by repeating the original function $ x(t) $ from $ t = [0,4] $ an infinite number of times.


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Alumni Liaison

Basic linear algebra uncovers and clarifies very important geometry and algebra.

Dr. Paul Garrett