Question 10

1. Given the following parameters, select the correct equation for the amplitude modulated (AM) carrier signal. A_m=2.5v, A_c=3v, f_m=3500Hz, f_c=120kHz, _m=0, _c=0

   		a. s(t) = 7[1+1.08 cos(23500t)] cos(2100E3t)
   		b. s(t) = 2.5[1+0.83 cos(23500t)] cos(2100E3t)
   		c. s(t) = 3[1+2.5 cos(23500t)] cos(2120t)
   		d. s(t) = 3[1+0.83 cos(23.5E3t)] cos(2120E3t)

Question 12

Given the following AM modulated signal, determine the original message, m(t):

s(t) = 2.5[1+0.5 cos(225kHzt)] cos(288MHzt)

		a. m(t) = 1.25cos(225kHz*t)
		b. m(t) = 1.25cos(288MHz*t)
		c. m(t) = 2.5cos(225kHz*t)
		d. m(t) = 2.5cos(288MHz*t)

Question 13

1. Given the following AM modulated signal, determine the occupied frequency bandwidth (note: assume double-sideband large carrier (DSB-LC):

   s(t) = 4[1+0.95 cos(23000t)] cos(2100E9t)

   		a. Frequency bandwidth = 3000 Hz
   		b. Frequency bandwidth = 6000 Hz
   		c. Frequency bandwidth = 100E9 Hz
   		d. Frequency bandwidth = 200E9 Hz

10 points

Question 14

1. Given the following message and carrier equations, determine the AM modulated signal equation: m(t)=3cos(24kHz*t), c(t)=2cos(23MHz*t)

   		a. s(t)=3[1 + 0.67cos(24000t)]cos(23E6t)
   		b. s(t)=2[1 + 1.5cos(24000t)]cos(23E6t)
   		c. s(t)=3[1 + 0.67cos(23E6t)]cos(24kHz*t)
   		d. s(t)=2[1 + 1.5cos(23MHz*t)]cos(24000t)

Question 18

1. Select the correct statement(s) regarding the FM Index.

   		a. f represents the amount of frequency that the carrier wave can change in order to represent the baseband (information/message) signal
   		b. =(KvcoAm)/fm is a ratio that has no units
   		c. the larger the FM index, the greater the frequency bandwidth
   		d. all statements are correct

10 points

Question 19

1. Given the following message, m(t), carrier, c(t), and Kvco=4300(Hz/v), determine the FM modulated signal equation and FM index. m(t)=2.5cos(24000t), c(t)=3cos(22GHz*t).

   		a. s(t)=2cos(25E6t + 1.56sin(23500t)), =1.56
   		b. s(t)=3cos(22E9t + 2.68sin(24E3t)), =2.68
   		c. s(t)=4cos(25E9t + 2.57sin(23500t)), =2
   		d. s(t)=4cos(23500t + 2.57sin(25MHz*t)), =2.57