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What is the carrier wave? Why high frequ...

What is the carrier wave? Why high frequency carrier waves are employed for transmission?

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A carrier wave is an electromagnetic wave of
high frequency and of constant amplitude, which
is employed to carry the audio signals from one
location to other on the surface of the earth.
For the transmission of audio signals, the high
frequency carrier wave are used, because these
high frequency carrier waves travel through
space or medium with the speed of light and
they are not obstructed by earth's atmosphere.
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