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Question
A message signal of frequency ωm is superposed on a carrier wave of frequency ωc to get an amplitude modulated wave (AM). The frequency of the AM wave will be ______.
Options
ωm
ωc
`(ω_"c" + ω_"m")/2`
`(ω_"c" - ω_"m")/2`
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Solution
A message signal of frequency ωm is superposed on a carrier wave of frequency ωc to get an amplitude modulated wave (AM). The frequency of the AM wave will be ωc.
Explanation:
The process of changing the amplitude of a carrier wave in accordance with the amplitude of the audio frequency (AF) signal is known as amplitude modulation (AM).
In AM, the frequency of the carrier wave remains unchanged or we can say that the frequency of a modulated wave is equal to the frequency of the carrier wave. Now, according to the problem, the frequency of the carrier wave is fc.
Thus the amplitude modulated wave also has frequency fc.
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