3 DEFINE MODULATION , NEED FOR MODULATION ?

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MODULATION :     

THE PROCESS OF CHANGING SOME CHARACTERISTICS OF CARRIER SIGNAL (AMPLITUDE  / FREQUENCY / PHASE)  IN ACCORDANCE WITH THE INSTANTANEOUS AMPLITUDE OF THE MESSAGE SIGNAL IS KNOWN AS MODULATION.








NEED FOR MODULATION :

I) REDUCE THE HEIGHT OF ANTENNA

II) FOR MULTIPLEXING

III) FOR EASY RADIATION

IV) AVOID MIXING OF SIGNALS

V) REDUCTION OF NOISE .




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