Forouzan Chapter 5 MCQ

Question 1

1. In ________, the amplitude of the carrier signal is varied to create signal elements. Both frequency and phase remain constant
   A) PSK C) FSK
   B) ASK D) QAM

Answer 1

ASK

Question 2

2. How many carrier frequencies are used in BPSK?
   A) 0 C) 2
   B) 1 D) none of the above

Answer 2

1

Question 3

3. The constellation diagram of 16-QAM has ______ dots.
   A) 4 C) 16
   B) 8 D) none of the above

Answer 3

16

Question 4

4. AM and FM are examples of ________ conversion.
   A) analog-to-analog C) analog-to-digital
   B) digital-to-digital D) digital-to-analog

Answer 4

analog-to-analog

Question 5

5. The Federal Communications Commission (FCC) allows ______ kHz for each FM station.
   A) 20 C) 200
   B) 100 D) none of the above

Answer 5

100

Question 6

6. Analog-to-analog conversion is needed if the available bandwidth is _______.
   A) band-pass C) either (a) or (b)
   B) low-pass D) neither (a) nor (b)

Answer 6

band-pass

Question 7

7. In _____ transmission, the frequency of the carrier signal is modulated to follow the changing voltage level (amplitude) of the modulating signal. The peak amplitude and phase of the carrier signal remain constant, but as the amplitude of the information signal changes, the frequency of the carrier changes correspondingly.
   A) AM C) PM
   B) FM D) none of the above

Answer 7

FM

Question 8

8. How many carrier frequencies are used in QPSK?
   A) 0 C) 1
   B) 2 D) none of the above

Answer 8

2

Question 9

9. Which of the following is not a digital-to-analog conversion?
   A) FSK C) AM
   B) ASK D) PSK

Answer 9

AM

Question 10

10. _______ conversion is the process of changing one of the characteristics of an analog signal based on the information in the digital data.
    A) Analog-to-analog C) Digital-to-analog
    B) Digital-to-digital D) Analog-to-digital

Answer 10

. Digital-to-analog

Question 11

11. If the baud rate is 400 for a QPSK signal, the bit rate is ________ bps.
    A) 100 C) 800
    B) 400 D) 1600

Answer 11

800

Question 12

12. In ________, the phase of the carrier is varied to represent two or more different signal elements. Both peak amplitude and frequency remain constant.
    A) PSK C) ASK
    B) FSK D) QAM

Answer 12

PSK

Question 13

13. Which of the following is not an analog-to-analog conversion?
    A) QAM C) PM
    B) AM D) FM

Answer 13

QAM

Question 14

14. How many carrier frequencies are used in BASK?
    A) 0 C) 2
    B) 1 D) none of the above

Answer 14

1

Question 15

15. Quadrature amplitude modulation (QAM) is a combination of ___________.
    A) PSK and FSK C) ASK and PSK
    B) ASK and FSK D) none of the above

Answer 15

ASK and PSK

Question 16

16. In _________, the frequency of the carrier signal is varied to represent data. Both peak amplitude and phase remain constant.
    A) ASK C) PSK
    B) FSK C) PSK

Answer 16

FSK

Question 17

17. If the bit rate for an ASK signal is 1200 bps, the baud rate is ________.
    A) 1200 C) 400
    B) 600 D) 300

Answer 17

1200

Question 18

18. The constellation diagram of BPSK has ______ dots.
    A) 0 C) 2
    B) 1 D) none of the above

Answer 18

2

Question 19

19. The constellation diagram of QPSK has ______ dots.
    A) 4 C) 1
    B) 2 D) none of the above

Answer 19

4

Question 20

20. In _______, the peak amplitude of one signal level is 0; the other is the same as the amplitude of the carrier frequency.
    A) OOK C) FSK
    B) PSK D) none of the above

Answer 20

OOK

Question 21

21. If the bit rate for a 16-QAM signal is 4000 bps, what is the baud rate?
    A) 1200 C) 400
    B) 1000 D) 300

Answer 21

1000

Question 22

22. ASK, PSK, FSK, and QAM are examples of ________ conversion.
    A) analog-to-analog C) analog-to-digital
    B) digital-to-digital D) digital-to-analog

Answer 22

digital-to-analog

Question 23

23. If the bit rate for an FSK signal is 1200 bps, the baud rate is ________.
    A) 1200 C) 400
    B) 600 D) 300

Answer 23

1200

Question 24

24. The constellation diagram of BASK has ______ dots.
    A) 0 C) 2
    B) 1 D) none of the above

Answer 24

2

Question 25

25. The Federal Communications Commission (FCC) allows ______kHz for each AM station.
    A) 20 C) 5
    B) 10 D) none of the above

Answer 25

10

Question 26

26. How many carrier frequencies are used in BFSK?
    A) 2 C) 0
    B) 1 D) none of the above

Answer 26

2

Question 27

27. In _____ transmission, the phase of the carrier signal is modulated to follow the changing voltage level (amplitude) of the modulating signal.
    A) AM C) PM
    B) FM D) none of the above

Answer 27

PM

Question 28

28. _________ conversion is the representation of analog information by an analog signal.
    A) Analog-to-analog C) Analog-to-digital
    B) Digital-to-digital D) Digital-to-analog

Answer 28

Analog-to-analog

Question 29

29. In _____ transmission, the carrier signal is modulated so that its amplitude varies with the changing amplitudes of the modulating signal.
    A) PM C) AM
    B) FM D) none of the above

Answer 29

AM

Question 30

30. In QAM, both ________ of a carrier frequency are varied.
    A) phase and frequency C) frequency and amplitude
    B) amplitude and phase D) none of the above

Answer 30

amplitude and phase

Question 31

31. ________ uses two carriers, one in-phase and the other quadrature.
    A) QAM C) FSK
    B) ASK D) PSK

Answer 31

QAM

Question 32

32. Given an AM radio signal with a bandwidth of 10 KHz and the highest-frequency component at 705 KHz, what is the frequency of the carrier signal?
    A) 710 KHz C) 700 KHz
    B) 705 KHz D) Cannot be determined from given information

Answer 32

700 KHz

Question 33

33. A constellation diagram shows us the __________ of a signal element, particularly when we are using two carriers (one in-phase and one quadrature).
    A) amplitude and frequency C) frequency and phase
    B) amplitude and phase D) none of the above

Answer 33

amplitude and phase

Question 34

34. If the baud rate for a 64-QAM signal is 2000, what is the bit rate?
    A) 12000 C) 400
    B) 1000 D) 300

Answer 34

12000