Question

A $10kW$ carrier is sinusoidally modulated by two carriers corresponding to a modulation index of $30\%$ and $40\%$ respectively. Then total power radiated by the modulator is

• A. $10.25kW$
• B. $11.25kW$
• C. $12.75kW$
• D. $17kW$

Answer 1

Answer: (B)

$11.25kW$

$P_c=\frac{{E_c}^2}{2}=10kW$
$m_a=\sqrt{m_1^2+m_2^2}=\sqrt{{0.30}^2+{0.40}^2}=0.50$
$\therefore P_t=P_c(1+\frac{{m_a}^2}{2})=10(1+\frac{{\left(0.5\right)}^2}{2})=11.25kW$