Question

No mathematical expression for x(t).

Problem 2: A message signal x(t), is illustrated in the graphs below x(t) 1.5 1 0.5 -1 3 -0.5 1 -1.5 Time (s) 2 1 -45 -30 -15 0 15 Frequency (kHz) This signal is applied to a Narrow Band FM generator as shown below; x(t) Ф. (t) NBFM 5.60 MHz. anda frequency deviation The NBFM Signal p(t) has a center frequency f Afi 2.4 kHz - A. Sketch the time-domain signal p1(t) using the segment of x() shown above as the input signal 45 30 St

Answer 1

Magnitude spectrum of Narrowband FM signal and A(amplitude modulation) signal are same.

message signal frequency = 15 kHz

Modulation index of Narrow band FM generator , $\beta$ = frequency deviation / message frequency = 2.4 k Hz/ 15 kHz = 0.16

message signal x(t) is sinusoidal signal.

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