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Jd303
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The input signal to an analog to digital converter is x(t) = 5.4 cos (134.5πt + 0.1π).
The output from the converter is y(n) = 5.4 cos (0.47πn - 0.1π).
Compute the sampling frequency (samples per second) of the analog to digital converter.
Hint: the continuous-time input signal is under-sampled in this case.
I have been doing questions like this recently, without too much trouble. However this one has me a little confused. I don't understand the theory behind how the value 0.1*pi changes to -0.1*pi in the output signal.
-If the output was 5.4cos(0.47*pi*n + 0.1*pi) I would do the following:
- fs = 2*134.5/0.47 = 572.34
-My attempt at this question is not much more than a guess, I have done:
3*fo - fs = 3*134.5 - 572.34 = 168.84
I would greatly appreciate anyone who is able to shed some light on this problem. Thanks!
The output from the converter is y(n) = 5.4 cos (0.47πn - 0.1π).
Compute the sampling frequency (samples per second) of the analog to digital converter.
Hint: the continuous-time input signal is under-sampled in this case.
I have been doing questions like this recently, without too much trouble. However this one has me a little confused. I don't understand the theory behind how the value 0.1*pi changes to -0.1*pi in the output signal.
-If the output was 5.4cos(0.47*pi*n + 0.1*pi) I would do the following:
- fs = 2*134.5/0.47 = 572.34
-My attempt at this question is not much more than a guess, I have done:
3*fo - fs = 3*134.5 - 572.34 = 168.84
I would greatly appreciate anyone who is able to shed some light on this problem. Thanks!