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A message signal of frequency ωm is superimposed on a carrier wave of frequency ωc to get an amplitude modulated wave (AM). The frequency of the AM wave will be:

A message signal of frequency ωm is superimposed on a carrier wave of frequency ωc to get an amplitude modulated wave (AM). The frequency of the AM wave will be: Correct Answer ω<sub>c</sub>

Concept –

Amplitude modulation –

  • It is the process in which the amplitude of the high-frequency carrier wave changes in accordance with the instantaneous value of modulating signals.
  • During the positive half of the modulating signals, the amplitude of the carrier wave increases, similarly during the negative half of the modulating signals, the amplitude of the carrier wave decreases.
  • The amplitude of the carrier wave changes according to the modulating signals.
  • The amplitude of the carrier wave changes at the frequency ‘fm’ of the modulating signal.
  • The frequency of the A.M. wave is equal to the unmodulated carrier frequency ‘fc’.

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Explanation –

Now, according to the problem, the frequency of the carrier wave is ωc. Thus the amplitude-modulated wave also has frequency ωc.

Related Questions

Consider the following statements regarding modulation : 1. The communication systems, where a weak signal is transmitted by the use of a modulation is essential in carrier signal. 2. When the frequency of the high frequency signal is varied in accordance with the intensity of the low-frequency weak signal, the modulation is said to be frequency modulation. 3. The process of recovering original baseband signal from the modulated signal is called phase modulation. Which of the above statements are correct ? 
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