Sinusoidal Fm (continued) ransmitted power does not depend on x(t): average power=A/2 Bandwidth ofy(t) can depend on amplitude of x(t) Demodulation a) Direct tracking of the phase at (by using phase-locked loop b) Use of an lti system that acts like a differentiator v(t y Envelope detector HG@- Tunable band-limited differentiator, over the bandwidth of y(t) H(j0)≈j 2()s looks like am (wc+ kf()Asin e(t) envelope detection de/ diSinusoidal FM (continued) • Transmitted power does not depend on x ( t): average power = A 2/2 • B a n d wid t h o f y ( t) can depend on amplitude of x ( t ) • Demodulation a) Direct tracking of the phase θ( t) (by using phase-locked loop ) b) Use of an LTI system that acts like a differentiator H(j ω) — Tunable band-limi ted differentiator, over the bandwidth of y ( t) … looks like AM envelope detection