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How Are Side Bands Produced? - Physics

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Question

How are side bands produced?

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Solution

Side bands are produced during the process of modulation.

During modulation, the audio frequency modulating signal wave is superimposed on a high frequency wave called carrier wave. Any form of modulation produces frequencies that are the sum and difference of the carrier and modulating frequencies. These frequencies are called as side bands.
 
                    
Lower side band frequency =  fc  fm
Upper side band frequency = fc + fm
 
where
fcCarrier wave frequency
 
fmModulating signal frequency 
 
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2014-2015 (March) Delhi Set 2

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