Question

This problem is on the basics of FM using single tone message. As we that certain message tone is modulated by Frequency Modulator is written as s(t)r'. 4 Cos [ 2 π 2000 t + 4 Sin (2x 10001 (a) Caleulate the maximum frequency deviation dfin (Hz](3) Hint: identify the value of B and use relation with freq. deviation) (b) Is this Wideband FM or Narrow band FM? (2) (c) Calculate the required transmission bandwidth Brl㎐l using Carson's rule (2) (you need to identify the message frequency m) to the behavior of Bessel function. Briefly explain how the magnitude of the side-lobes change as frequency increases as of function of 'n' (at frequency fe +n fa). Use the Bessel function Table distributed. (3) (hint: 1st side-lobe means n-1, hence its magnitude is (1/2) AdJi(B). See the behavior of (d) In theory, FM requires infinite transmission bandwidth, but in fact not much is needed due Ja(B) from the Table or curve.)

Answer 1