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| + | [[Homework 2_ECE301Fall2008mboutin]] - [[HW2-A Phil Cannon_ECE301Fall2008mboutin|'''A''']] - [[HW2-B Phil Cannon_ECE301Fall2008mboutin|'''B''']] - [[HW2-C Phil Cannon_ECE301Fall2008mboutin|'''C''']] - [[HW2-D Phil Cannon_ECE301Fall2008mboutin|'''D''']] - [[HW2-E Phil Cannon_ECE301Fall2008mboutin|'''E''']] | ||
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== Periodic Signals Revisited == | == Periodic Signals Revisited == | ||
1. By sampling at different frequencies the signal <math>y=sin(x)\!</math> can appear as both periodic and non-periodic in DT. For example: | 1. By sampling at different frequencies the signal <math>y=sin(x)\!</math> can appear as both periodic and non-periodic in DT. For example: | ||
Revision as of 10:09, 12 September 2008
Homework 2_ECE301Fall2008mboutin - A - B - C - D - E
Periodic Signals Revisited
1. By sampling at different frequencies the signal $ y=sin(x)\! $ can appear as both periodic and non-periodic in DT. For example:
$ y(x)=sin(x) \! $ in CT
$ y[n]=sin[n] \! $ with a sample rate of 1
$ y[n]=sin[n] \! $ with a sample rate of $ pi/4 \! $
The second graph has no integer value of N where y[n]=y[n+N], thus it is non-periodic.
The third graph clearly shows there is an integer value of N where y[n]=y[n+N], thus it is periodic.
2. By adding up several 10 unit cycles of the function $ y(x)=x^2\! $ we can turn a non-periodic signal into a periodic signal:
