1) Reception 
Demodulation is the act of extracting the original information-bearing signal from a modulated carrier wave. A demodulator is an electronic circuit (or computer program in a software-defined radio) that is used to recover the information content from the modulated carrier wave The demodulator takes the digital data and, using the staircase maker a...
To extract information from a modulated carrier wave.
the process of recovering the original modulating signal from a modulated signal
Re-creation of an original data stream from a modulated signal.
Reversing the modulation process on reception of a radio signal to extract the baseband signal.
[n] - (electronics) the reception of a signal by extracting it from the carrier wave
The process of recovering intelligence from a signal, some parameter of which was modified to carry the intelligence. 
noun (electronics) the reception of a signal by extracting it from the carrier wave
Process of returning a modulated signal to its original form. Modems perform demodulation by taking an analog signal and returning it to its original (digital) form. See also modulation.
detection (def. 4b).