 The 90Hz has decreased a lot by the low pass filter.
Then the decimator becomes effective. Open a monitor for TXTOUT(U_9) to
see the results of decimation.
Only 10Hz has been picked up!!
Let's see the FFTMON(U_10) for the spectrum. 10Hz remains but 95Hz has
decreased and moved to 5Hz by decimation. (95Hz is unable to live in the
world Fs = 100Hz)
That's it for this class. If you do decimation, you need to be careful
of how the spectrum lives in the frequency domain. If there are some frequencies higher than Nyquist frequency, you should remove them
by a LPF before decimator. Otherwise a high frequency may transform itself into a low frequency.
You can also refer to "Basis of Over Sampling".
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