3.2.3. Consider the demodulator shown below. The input is DSB-LC AM. As usual, fc B,
where B is the bandwidth of m(t).
s(t) = (A + m(t)) cos(2πfct) ✲ | · | ✲
x(t) y(t)✲ ?
z(✲t) = am(t)
(a) Using the fact that | cos(2πfct)| =
cos(4πnfct), determine a formula
for x(t) that has no absolute values. Hint: For DSB-LC, A + m(t) ≥ 0.
(b) Determine a formula for y(t).
(c) What should the final block subtract so as to obtain z(t) = am(t)? What is a?
Leave an answer