If \(E_c\) and \(E_m\) are peak values of carrier and modulating signals, respectively then for \(100 \%\)…

If \(E_c\) and \(E_m\) are peak values of carrier and modulating signals, respectively then for \(100 \%\) modulation,
  1. \(E_c=\frac{E_m}{2}\)
  2. \(\frac{E_c^2}{2}=E_m^2\)
  3. \(E_{\mathrm{c}}=E_m\)
  4. \(E_c=2 E_m\)

Solution

Key idea Modulation index of a modulated signal is \(\mu=\frac{E_m}{E_c}\) Where, \(E_m\) and \(E_c\) are peak values of modulating signal and carrier signal. For \(100 \%\) modulation, modulation index should be unity. Hence, \(\mu=1=\frac{E_m}{E_c}\) \(\Rightarrow \quad E_m=E_c\) \(\therefore\) The correct option is (c).

Asked in: AP EAMCET 2019 (23 Apr Shift 1)

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