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Frequency and Phase Sensitivity of a Modulated Signal 1. General Angle-Modulated Signal $$ s(t) = A_c \cos[\theta(t)] $$ $$ \theta(t) = \omega_c t + \phi(t) $$ 2. Frequency Sensitivity (FM) $$ f_i(t) = \frac{1}{2\pi} \frac{d\theta(t)}{dt} $$ $$ f_i(t) = \frac{1}{2\pi} \left(\omega_c + \frac{d\phi(t)}{dt}\right) $$ For FM: $$ \phi(t) = k_f \int m(t)\,dt $$ $$ f_i(t) = f_c + \frac{k_f}{2\pi} m(t) $$ $$ k_f = \frac{d\omega_i(t)}{dm(t)} $$ 3. Phase Sensitivity (PM) $$ \phi(t) = k_p m(t) $$ $$ f_i(t) = f_c + \frac{k_p}{2\pi} \frac{dm(t)}{dt} $$ $$ k_p = \frac{d\phi(t)}{dm(t)} $$ 4. Example Signal Analysis Given Signal $$ x(t) = 3\cos\left[2\pi \cdot 10^6 t + 2\sin(2\pi \cdot 10^3 t)\right] $$ Step 1: Identify Components Carrier amplitude: \( A_c = 3 \) Carrier frequency: \( f_c = 10^6 \) Hz Modulating frequency: \( f_m = 10^3 \) Hz Step 2: Compare with Standard FM Form Standard FM form: $$ x(t) = A_c \cos\left...