# Data Communication and Networking – Digital to Analog Encoding / Modulation Techniques – ASK / FSK / PSK / QAM MCQs A+ A  A-

This set of Data communication and Networking Multiple Choice Questions and Answers (MCQs) focuses on “Digital to Analog to Encoding / Modulation Techniques – Amplitude-shift keying (ASK)- Frequency-shift keying (FSK)- Phase-shift keying (PSK)- Quadrature Amplitude Modulation(QAM)”.

1
. The process of changing one of the characteristics of a carrier analog signal based on the information in a digital signal is called _______ conversion
• analog-to-analog
• analog-to-digital
• digital-to-analog
• digital-to-digital
2
. In _______ the frequency of the carrier signal is varied based on the information in a digital signal
• ASK
• PSK
• FSK
• QAM
3
. In _______ the amplitude of the carrier signal is varied based on the information in a digital signal.
• ASK
• PSK
• FSK
• QAM
4
. In _______ the phase of the carrier signal is varied based on the information in a digital signal
• ASK
• PSK
• FSK
• QAM
5
. In _______ the phase and amplitude of the carrier signal is varied based on the information in a digital signal.
• ASK
• PSK
• FSK
• QAM
6
. Most modern modems use _______ for digital to analog modulation
• ASK
• PSK
• FSK
• QAM
7
. _______ rate is the number of bits per second; _______ rate is the number of signal units per second
• Baud; bit
• Bit; baud
• Baud; base
• Base; baud
8
. _______ rate is always less than or equal to _______ rate
• Baud; bit
• Bit; baud
• Baud; base
• Base; baud
9
. If the bit rate is 1200 bps and there are 4 bits for each signal element, then the baud rate is _______.
• 4800
• 1200
• 400
• 300
10
. If the baud rate is 1200 and there are 4 bits for each signal element, then the bit rate is _______
• 4800
• 1200
• 400
• 300
11
. An ASK modulated signal has a bit rate of 2000 bps; the baud rate is _______
• 2000
• 1000
• 4000
• none of the above
12
. A 2-PSK modulated signal has a bit rate of 2000 bps; the baud rate is _______
• 2000
• 1000
• 4000
• none of the above
13
. A 4-PSK modulated signal has a bit rate of 2000 bps; the baud rate is _______.
• 2000
• 1000
• 4000
• none of the above
14
. An 8-PSK modulated signal has a baud rate of 2000; the bit rate is _______ bps
• 8000
• 6000
• 2000
• 1000
15
. An 8-QAM modulated signal has a baud rate of 2000; the bit rate is _______ bps
• 8000
• 6000
• 2000
• 1000
16
. A 32-QAM modulated signal has a baud rate of 2000; the bit rate is _______ bps
• 16000
• 10000
• 4000
• 1000
17
. A 128-QAM modulated signal has a baud rate of 2000; there are _______ bits per baud.
• 2000
• 1000
• 7
• 6
18
. A 256-QAM modulated signal has a bit rate of 8000; there are _______ bits per baud
• 8000
• 4000
• 8
• 7
19
. OOK is a type of _______ modulation.
• ASK
• PSK
• FSK
• QAM
20
. The modulation technique most affected by noise is _______
• ASK
• PSK
• FSK
• QAM
21
. For _______, the minimum bandwidth required for transmission is equal to the baud rate
• ASK
• PSK
• FSK
• a and b
22
. The minimum bandwidth for an ASK modulated signal with a baud rate of 5000 is _______ Hz.
• 1000
• 2500
• 5000
• 10000
23
. On a 16-QAM-constellation diagram, each constellation point represents a _______
• dibit
• tribit
• quadbit
• pentabit
24
. In which type of modulation can the bit rate be four times the baud rate?
• ASK
• FSK
• PSK
• None of the above
25
. In which type of modulation can the bit rate be three times the baud rate?
• ASK
• FSK
• PSK
• None of the above
26
. In which type of modulation can the bit rate be half the baud rate?
• ASK
• FSK
• PSK
• None of the above
27
. In _______ modulation, the bit rate is 8 times the baud rate
• 8-QAM
• 64-QAM
• 256-QAM
• None of the above
28
. In _______ modulation, the baud rate is 1/4 times the bit rate.
• 4-QAM
• 2-PSK
• 4-PSK
• None of the above
29
. In a dibit modulation, the number of points in the constellation is _______
• 2
• 4
• 8
• None of the above
30
. In a tribit modulation, the number of points in the constellation is _______
• 2
• 4
• 8
• None of the above
31
. A 4-PSK constellation is a _________ modulation
• dibit
• tribit
• quadbit
• None of the above
32
. An 8-QAM constellation is a _________ modulation
• dibit
• tribit
• quadbit
• None of the above
33
. The number of points in the constellation of an 8-PSK modulation is _______ the number of points for an 8-QAM
• greater than
• less than
• equal to
• None of the above
34
. If the baud rate for modulation scheme A is two times the baud rate for modulation scheme B, the required bandwidth for scheme A is ___________ the one for scheme B
• more than
• less than
• equal to
• we cannot tell
35
. If the bit rate for modulation scheme A is two times the bit rate for modulation scheme B, the required bandwidth for scheme A is ___________ the one for scheme B.
• more than
• less than
• equal to
• we cannot tell