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In this experiment we take a closer look on a sinc-pulse. Especially the relationship between the pulse shape (time domain) and the spectrum (frequency domain).
At first we should focus on the sinc-pulse itself. The fundamental parameters are the impulse height or amplitude and the impulse width.
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In this example the sinc-pulse is high and wide.
The spectrum has similar parameters. More particularly its width and cutoff frequency. To view the whole spectrum the negative frequencies have to be visualized.
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As you can see, the spectrum width is twice the cutoff frequency .
Start
Start the experiment and have a look on the oscilloscope and the spectrum analyzer.
Now open the filter properties dialogue and change the cutoff frequency to .
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Look how the pulse shape and spectrum change. What relationship do you see?
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Finally change the impulse response length and look at the oscilloscope and spectrum analyzer.
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How does this affect the pulse shape and spectrum?
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Next
Also take a look at the other simulation apps to get further into signals and spectra.