An AM modulator operates with the message signal: m(t) = 9 cos(20πt) - 8 cos(60πt).
The unmodulated carrier is given by 110 cos(200πt), and the system operates with an index of 1/2.
a. Write the equation for mn(t), the normalized signal with a minimum value of -1.
b. Determine (m2n(t)), the power in mn(t).
c. Determine the efficiency of the modulator.
d. Sketch the double-sided spectrum of xc(t), the modulator output, giving the weights and frequencies of all components.