Amplitude modulation (AM) is applied to a message signal m(t) to generate amplitude modulated signal SAM(t) with modulation index m = 0.7. The carrier is c(t) = cos(200000.mt) and amplitude spectrum of the message signal M(f) is depicted in Fig.1. (a) Find the amplitude modulated signal SAM (t). (b) Find and draw frequency spectrum of the amplitude modulated signal. SAM(f) = ? (c) Design and sketch block diagram of a coherent demodulator to obtain the m(t). (d) Show that with the demodulator designed in 1(c), m(t) can be fully obtained. M(f) M -10 1 Fig.1 f(kHz) !!!