Question

QUESTION 5Select the correct statement(s) regarding amplitude modulation (AM).

		a. If the AM Index is greater than 1 (i.e., µAM>1), then over modulation occurs leading to signal distortion
		b. With AM, the message is captured as amplitude changes to the carrier’s amplitude.
		c. The AM modulated signal bandwidth is dependent upon the highest frequency (fm), and frequency bandwidth, of the message
		d. All of the above are correct

QUESTION 6

1. Amplitude Modulation (AM) describes a method where the baseband message is represented by carrier’s frequency.

True

False

QUESTION 8

1. Given the following parameters, select the correct equation for the modulated carrier signal. A_m=3v, A_c=3v, f_m=5500Hz, f_c=100MHz, φ_m=0, φ_c=0

		a. s(t) = 3[1+1.08 cos(2π5500t)] cos(2π100E6t)
		b.s(t) = 3[1+1cos(2π5500t)] cos(2π100E6t)
		c.s(t) = 3[1+6.5 cos(2π3500t)] cos(2π100t)
		d. s(t) = 6.5[1+0.93 cos(2π100t)] cos(2π100E3t)

Answer 1

5:
d)All the above are correct

6)
False
This is because in AM baseband message is represented by carrier's amplitude and not its frequency

7) b.s(t) = 3[1+1cos(2π5500t)] cos(2π100E6t)
modulated carrier signal is given by:
s(t) =[Ac +Am*cos(2*pi*fm*t)]*cos(2*pi*fc*t)
putting values:
s(t) = [3 + 3*cos(2*pi*5500)]cos(2*pi*100E6*t)
which is option b