Consider a narrow b and FM signal approximately defined by s (t) = A_c cos (2??_ct) ? ?A_c sin (2??_ct) sin (2??_mt)

(a) Determine the envelope of this modulated signal. What is the ratio of the maximum to the minimum value of this envelope? Plot this ratio versus ?, assuming that ? is restricted to the interval 0 ? 0.3.

(b) Determine the envelope of this modulated signal. What is the ratio of the maximum to the minimum value of this envelope? Plot this ratio versus ?, assuming that ? is restricted to the interval 0 ? 0.3.

(c) By expanding the angle ?_i (t) of the narrow-band FM signal s (t) in the form of a power series, and restricted the modulation index ? to a maximum value of 0.3 radians, show that. What is the power ratio of third harmonic to fundamental component for ? = 0.3?

Transcribed Image Text:

sin (2nft) 0,(t) - 2nf.t + ß sin(27ft)