Question

If modulation is $100\%$, what will be the useful part of total power?

• A. $\frac{1}{2}$
• B. $\frac{2}{3}$
• C. $\frac{1}{3}$
• D. $\frac{4}{3}$

Answer 1

The correct option is C $\frac{1}{3}$

$\frac{Usefulpower}{Totalpower}=\frac{{m_a}^2}{2+{m_a}^2}$
For $m_a=100\%$, $\frac{Usefulpower}{Totalpower}=\frac{1}{2+1}=\frac{1}{3}$
$⟹Usefulpower=\frac{1}{3}totalpower$.