Describe amplitude shift keying (ASK) modulation with suitable circuit diagram.

Describe amplitude shift keying (ASK) modulation with suitable circuit diagram.
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1 Answer

Answer :

Explanation:-

ASK MODULATOR:

The process where a binary information signal directly modulates the amplitude of an analog carrier. The digital signal is used to switch the carrier between amplitude levels is called Amplitude Shift Keying (ASK).

The ASK technique of binary modulation is illustrated in Figure where modulating signal consists of unipolar pulses. Because in this case the carrier is switched ON and OFF, this method is also known as ON-OFF keying.

For the entire time the binary input is high, the output is a constant amplitude, constant frequency signal and for the entire time the binary input is low, the carrier is off.

ASK is given by:

image


Block diagram of ASK Transmitter / ASK modulator:- 

image

Waveforms:- 

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