1. Consider a single-tone AM signal with m(t) = 3 cos 400mt and c(t) = 10...

  

Transcribed Image Text:

1. Consider a single-tone AM signal with m(t) = 3 cos 400mt and c(t) = 10 cos(10000mt). Let k, = 0.2. Find power in s(t)= (1+ kam(t)) c(t). (i) Calculate AM efficiency defined as NAM (ii) Plot the spectrum S(f). Power in Side tones Total Power in s(t) sin² 400xt 2. Consider an AM signal with m(t) 212 spectra of (1) M(f) (ii) C(f) and (iii) S(f). M x 100. and e(t) = 10 cos(10000 t). Let ka -0.2. Plot the 3. Let the signal (t) = A. [1+kum(t)] cos 2n fet be fed to a nonlinear device that produces an output v₂(t)= a(t) + ₂vi (t). Find the conditions for which the message m(t) my be recovered from v₂ (t). 4. Problem 3-2 from the textbook. 5. Show that a synchronous demodulator can also demodulate an AM signal. Let s(t)= {1+kam(t)) c(t). Assume that cos 2a fet is available in a local oscillator. By multiplying s(t) with cos 2n fet, and by filtering we can get m(t). Draw a schematic for this method and explain. 1. Consider a single-tone AM signal with m(t) = 3 cos 400mt and c(t) = 10 cos(10000mt). Let k, = 0.2. Find power in s(t)= (1+ kam(t)) c(t). (i) Calculate AM efficiency defined as NAM (ii) Plot the spectrum S(f). Power in Side tones Total Power in s(t) sin² 400xt 2. Consider an AM signal with m(t) 212 spectra of (1) M(f) (ii) C(f) and (iii) S(f). M x 100. and e(t) = 10 cos(10000 t). Let ka -0.2. Plot the 3. Let the signal (t) = A. [1+kum(t)] cos 2n fet be fed to a nonlinear device that produces an output v₂(t)= a(t) + ₂vi (t). Find the conditions for which the message m(t) my be recovered from v₂ (t). 4. Problem 3-2 from the textbook. 5. Show that a synchronous demodulator can also demodulate an AM signal. Let s(t)= {1+kam(t)) c(t). Assume that cos 2a fet is available in a local oscillator. By multiplying s(t) with cos 2n fet, and by filtering we can get m(t). Draw a schematic for this method and explain.