Mani Raj Paul - Modulation

What is Modulation?

Modulationis the process of changing the parameters of the carrier signal, in accordance with the instantaneous values of the modulating signal.

Need for Modulation

The baseband signals are incompatible for direct transmission. For such a signal, to travel longer distances, its strength has to be increased by modulating

Advantages of Modulation

  • Antenna size gets reduced.
  • No signal mixing occurs.
  • Communication range increases.
  • Multiplexing of signals occur.
  • Adjustments in the bandwidth is allowed.
  • Reception quality improves.

Message  Signal

The signal which contains a message to be transmitted, is called as a message signal.

Carrier Signal

The high frequency signal which has a certain phase, frequency, and amplitude but contains no information, is called a carrier signal.

Modulated Signal

The resultant signal after the process of modulation, is called as the modulated signal.

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