 Let's open a monitor for another FFTMON (U_20).
High frequencies are reduced a lot.
So how is the wave?? Please open WAVOUT (U_16).
The Base Band has come back!! This is pure 300Hz with some DC offset.
You can listen to the sound by choosing "Tools" -> "Play
Wave" on the menu.
That's it for this class. Taking absolute value of modulated signal is the simplest way of AM demodulation. How to get
the absolute value, we often use diodes in analog demodulator. In digital,
we just convert the polarity if it has negative value.
In next class, we use a multiplier to demodulate it.
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