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Question
Explain the process of amplitude modulation.
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Solution
Amplitude Modulation: Amplitude modulation is produced by varying the amplitude of the carrier waves in accordance with the amplitude of the modulating wave.
Let the carrier wave be c(t) = Acsinωct and the modulating signal be m(t) = Amsinωmt where ωm = 2πfm is the angular frequency of the message signal.
Modulated signal cm(t) is
cm(t)=(Ac+Am sinωmt)sinωct
where μ = Am/Ac is the modulation index.
`c_m(t)=A_csinomega_ct+(muA_c)/2cos(omega_c-omega_m)t-(muA_c)/2cos(omega_c+omega_m)t`
ωc - ωm and ωc+ωm are the lower side and upper side frequencies, respectively.
Production of Amplitude Modulated Wave
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