amplitude modulation and demodulation
DESCRIPTION
amTRANSCRIPT
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Name-nishant kumar
Roll-213ec5246
AIM:
Design of Amplitude Modulator and Demodulator using TMS Processor
THEORY:
Amplitude Modulation
Introduction
Amplitude Modulation is a technique used in electronics communication for
transmitting information via a carrier wave. It works by varying the strength of the
transmitted signal in relation to the information being sent.
Modulation
Modulation is the process whereby some characteristics of one wave is varied in
accordance with characteristics of another wave. In other words we can say that
modulation is the process of mixing or addition of information signal with an electronic or
optical carrier.
Carrier
The sinusoidal signal that is used in the modulation is known as carrier signal or carrier.
A carrier wave or carrier is a waveform that is modulated with an input signal for the
purpose of conveying information. This carrier wave is usually a much higher
frequency.
Signal
A signal is a real or complex valued function of one or more real variables. A signal is
an electric current or electromagnetic field used to convey data, gesture, action or
sound from one place to another place. The signal is said to be one dimensional.
Here the mathematical model that defines the AM signal is
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AM = ( DC + Message ) * the carrier Classification of AM modulated signals: 1) DSB-FC (Double side band Full Carrier) 2) DSB-SC(Double side band suppressed Carrier) 3) SSB(Single side band ) 4)VSB(Vestigial sideband)
Amplitude Demodulation
If we've completed AM Modulation then we've seen what happens when a
sinewave is used to amplitude modulate a carrier to produce an AM signal.
Importantly, we would have seen a key characteristic of an AM signal - its
envelopes are the same shape as the message ( though the lower envelope is
inverted ).
Recovering the original message from a modulated carrier is
called demodulation . We use envelope detector and synchronous detector for
demodulation.
Simulink
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Results:-
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Demod