110 Mobile and Wireless Technology MCQ's

Mobile and Wireless Technology 110 Objective Questions

1. Typical speech power

• A. 10 to 1000 µW
• B. 100 to 1000 mW
• C. 10 to 1000 nW
• D. 100 to 1000 pW

2. The maximum intelligibility for voice frequency is located between

• A. 250 and 500 Hz
• B. 1000 and 3000 Hz
• C. 500 and 1000 Hz
• D. 3000 and 5000 Hz

3. The maximum voice energy is located between

• A. 250 and 500 Hz
• B. 1000 and 3000 Hz
• C. 500 and 1000 Hz
• D. 3000 and 5000 Hz

4. A device used to measure speech volume.

• A. speech meter
• B. volume meter
• C. volume unit meter
• D. speedometer

5. By definition, for a sine wave

• A. 0 dBm = 0 V.U.
• B. 0 dBW = 0 V.U.
• C. 0 dBa = 0 V.U.
• D. 0 dBf = 0 V.U.

6. Presently, this is the “standard” frequency bandwidth for voice transmission.

• A. 0 to 4000 Hz
• B. 100 to 3400 Hz
• C. 300 to 3400 Hz
• D. 300 to 3000 Hz

7. Which of the following is commonly used wire for subscriber loop design?

• A. AWG # 19
• B. AWG # 18
• C. AWG # 30
• D. AWG # 33

8. The resistance limit for No. 2 Crossbar Exchange (US) is

• A. 1300 Ω
• B. 2000 Ω
• C. 1250 Ω
• D. 1200 Ω

9. AWG # 26 has a typical loss of

• A. 0.21 dB/1000 ft.
• B. 0.32 dB/1000 ft.
• C. 0.41 dB/1000 ft.
• D. 0.51 dB/1000 ft.

10. What is the standard voice channel spacing?

• A. 44 MHz
• B. 40 kHz
• C. 4 kHz
• D. 40 MHz

11. Which tester is used to measure SWR?

• A. Multimeter
• B. Oscilloscope
• C. Spectrum analyzer
• D. Reflectometer

12. What is singing?

• A. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency equal to the sum of the frequencies of the signals intermodulated.
• B. The result of intermodulating two or more signals of different frequencies to produce a tone having a frequency higher than that of the signal having the highest frequency.
• C. An undesired self-sustained oscillation in a system, generally caused by excessive positive feedback.
• D. An art or form of entertainment that can make one rich.

13. Which stage increases the selectivity of the circuit in an AM receiver?

• A. Detector
• B. IF stage
• C. Modulator
• D. Mixer

14. The ________ of radio receiver amplify weak signal and produce a desirable intelligence at the output speaker.

• A. sensitivity
• B. selectivity
• C. reliability
• D. fidelity

15. Full-duplex transmission means

• A. One-way transmission
• B. 24-hour transmission
• C. Broadcast transmission
• D. Two-way simultaneous transmission

16. What is a multidrop line?

• A. A piece of wire with a thick insulating material that serves to protect the conductive materials from damage in the event the wire is dropped.
• B. A line designed to withstand high pressure.
• C. A line or circuit interconnecting several situations.
• D. A bus line

17. A passive _________ is an electronic device which reduces signal strength by a specified amount in dB.

• A. Splitter
• B. Filter
• C. Trimmer
• D. Attenuator

18. The signal quality of the calls is constantly monitored by the base station, when the quality of the calls drops below a certain specified level. The base request the MTSO to try and find a better cell site.

• A. Hand-off
• B. Cell splitting
• C. Roaming
• D. Frequency reuse

19. A digital identification associated with a cellular system.

• A. SAT
• B. SID
• C. ESN
• D. MIN

20. How many seconds does facsimile transmit a stranded page?

• A. 5
• B. 10
• C. 20
• D. 25

21. A kind of recording used in facsimile.

• A. Electrolytic recording
• B. Electrothermal recording
• C. Electropercussive recording
• D. Electrostatic recording

22. A type of distortion a facsimile produce when it becomes out of synchronization?

• A. Pincushion
• B. Barrel
• C. Skewing
• D. Fattening

23. What is an acoustic coupler?

• A. A device that radiates audible signals via a transmitting antenna
• B. A device that converts electric signals into audio signals, enabling data to be transmitted over the public telephone network via a conventional telephone handset
• C. A device that receives audible signals and retransmits them at VHF frequencies
• D. A transducer

24. Cause a herringbone pattern in facsimile

• A. Single-frequency interference
• B. Crosstalk
• C. Phase jitter
• D. Noise

25. The _______ in an FM receiver causes a stronger signal to dominate over a weaker signal on the same frequency.

• A. Capture effect
• B. Flywheel effect
• C. Hall effect
• D. Skin effect

26. A device that converts a 2-wire circuit to a 4-wire circuit.

• A. RS-232 interface
• B. Hybrid circuit
• C. Balun
• D. Stub

27. ______ theory is deciding between a set of hypothesis when given a collection of imperfect measurements.

• A. Estimation
• B. Traffic
• C. Decision
• D. Nyquist

28. ______ of a data reduction says that when reducing a set of data into the form of an underlying mode, one should be maximally non-committal with respect to missing data.

• A. Jaynes maximum entropy principle
• B. Kullback principle of minimum discrimination
• C. Minimum discrimination\
• D. Maximum entropy

29. _______ is selecting the best value of a parameter from a continuum of possible values when gives a collection if imperfect measurements

• A. Estimation
• B. Traffic
• C. Decision
• D. Nyquist

30. Combination of madulator, channel, and detector.

• A. Transceiver
• B. Transponder
• C. T/R channel
• D. Discrete channel

31. What is the frequency band of DECT?

• A. 1.88 – 1.90 GHz
• B. 1.68 – 1.70 GHz
• C. 1.48 – 1.50 GHz
• D. 1.28 – 1.30 GHz

32. How many simultaneous calls does each DECT system can support?

• A. 96
• B. 12
• C. 24
• D. 49

33. How many simultaneous calls does a DECT radio transceiver can assess at any given time?

• A. 120
• B. 240
• C. 480
• D. 960

34. The AGC voltage of a radio receiver is always _______.

• A. Present before adjustments can be made
• B. DC, but may have either polarity positive DC
• C. Positive DC
• D. Negative

35. What is a concentrator?

• A. A system that improves the signal-to-noise ratio by compressing the volume range of a signal.
• B. A device that varies the characteristics of a carrier signal in accordance with the waveform of a modulating signal which contains useful information
• C. A switching system that lets a large number of telephone or data processing subscribers use a lesser number of transmission lines or a narrow bandwidth
• D. Equipment in the central office.

36. If you find that an SAW filter output is 6 dB down from the input of a receiver during test, ______

• A. This is normal.
• B. The device if faulty
• C. The receiver is improperly terminated
• D. The filter is not resonating

37. A triple conversion superheterodyne receiver, diode mixer stages are

• A. Operated in the linear region
• B. Operated in the nonlinear region
• C. Operated as Class-A amplifiers
• D. Operated as Class-B amplifiers

38. What is a leased line?

• A. A piece of wire used in a local area network in one building
• B. A piece of wire connecting a telephone set to a PABX
• C. A temporary connection of one computer to a mainframe via a modern and a telephone line
• D. A permanent circuit for a private use within a communication network

39. If two FM signals of different strengths are received on the same frequency

• A. One steady heterodyne will appear in the AM output
• B. Both will appear in the AF output
• C. Only the stronger will appear in the AF output
• D. Neither signal will be intelligence unless the weaker signal is at least 10 times

40. Cellular mobile system was first operated in

• A. 1979
• B. 1981
• C. 1983
• D. 1985

41. TACS is a cellular system with ______ channels.

• A. 666
• B. 1000
• C. 832
• D. 200

42. Supervisory Audio Tone (SAT) has _______ frequency.

• A. 5960 Hz
• B. 6000 Hz
• C. 6040 Hz
• D. 1004 z

43. What is the number of channels of a cellular system with an allocated spectrum of 25 MHz and with a channel of 30 kHz bandwidth?

• A. 833
• B. 240
• C. 1000
• D. 666

44. GSM uses what digital modulation technique?

• A. QAM
• B. GFSK
• C. BPSK
• D. GMSK

45. What is the power output of Personal Communication System (PCS)?

• A. 10 mW
• B. 75 mW
• C. 150 mW
• D. 10 W

46. RG-B8 cable has a loss of about ______ dB at cellular frequencies up to 15 ft. length.

• A. 2
• B. 1
• C. 4
• D. 3

47. The signals designed to keep the receivers and transmitters aligned.

• A. Carrier frequencies
• B. Pilot carrier signals
• C. Synchronizing signals
• D. Reference signals

48. If the spacing of a two-wire open air transmission line is 12 inches and the conductor diameter is 0.25 inch, the characteristic impedance is

• A. 547 Ω
• B. 357 Ω
• C. 273 Ω
• D. 300 Ω

49. The impedance of the quarterwave transformer used to match a 600 Ω line to a 300 Ω load is

• A. 382 Ω
• B. 424 Ω
• C. 565 Ω
• D. 712 Ω

50. When a line and a load are match the reflection coefficient is

• A. Unity
• B. Zero
• C. Positive infinity
• D. Negative infinity

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Answers(1-50 SET1):
1. 10 to 1000 µW
2. 1000 and 3000 Hz
3. 250 and 500 Hz
4. volume unit meter
5. 0 dBm = 0 V.U.
6. 300 to 3400 Hz
7. AWG # 19
8. 1300 Ω
9. 0.51 dB/1000 ft.
10. 4 kHz
11. Reflectometer
12. An undesired self-sustained oscillation in a system, generally caused by excessive positive feedback.
13. IF stage
14. sensitivity
15. Two-way simultaneous transmission
16. A line or circuit interconnecting several situations.
17. Attenuator
18. Roaming
19. MIN
20. 25
21. Electrolytic recording
22. Skewing
23. A device that converts electric signals into audio signals, enabling data to be transmitted over the public telephone network via a conventional telephone handset
24. Crosstalk
25. Capture effect
26. Hybrid circuit
27. Decision
28. Jaynes maximum entropy principle
29. Estimation
30. Discrete channel
31. 1.88 – 1.90 GHz
32. 12
33. 120
34. DC, but may have either polarity positive DC
35. A switching system that lets a large number of telephone or data processing subscribers use a lesser number of transmission lines or a narrow bandwidth
36.  This is normal.
37. Operated in the nonlinear region
38. A permanent circuit for a private use within a communication network
39. Only the stronger will appear in the AF output
40. 1983
41. 1000
42. 6000 Hz
43. 833
44. GFSK
45. 10 mW
46. 3
47. Pilot carrier signals
48. 547 Ω
49. 424 Ω
50. Zero

 

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51. When line is terminated in an open circuit load, the reflection coefficient is

• A. Unity
• B. Zero
• C. Positive infinity
• D. Negative infinity

52. A 300 ohms line is terminated in a resistance load of 200 ohms, the VSWR is

• A. 0.65
• B. 1.5
• C. Unity
• D. Zero

53. If the reflection coefficient is 0.5, the standing wave ratio is

• A. 0.33
• B. Unity
• C. 3
• D. Zero

54. To least the fault of the given line, a signal is fed to the line, 30 µs later the signal returned. What is the distance of the fault?

• A. 9000 m
• B. 300 m
• C. 100 m
• D. 4500 m

55. The telephone set is powered by the central office on the ring side at

• A. 42 to 52 Vdc
• B. – 42 to -52 Vdc
• C. 24 to 64 Vdc
• D. – 24 to – 64 Vdc

56. The telephone voice band frequency is from

• A. 300 to 4 kHz
• B. 400 to 3400 Hz
• C. 300 to 3400 Hz
• D. 400 to 4 kHz

57. Which of the following wire is used to transmit the signal?

• A. Black
• B. Yellow
• C. Red
• D. Green

58. The corresponding frequency for digit 7 in the touch tone telephone is

• A. 770 & 1477 Hz
• B. 852 & 1209 Hz
• C. 852 & 1336 Hz
• D. 770 & 1336 Hz

59. The physical connection between the telephone set and the switching equipment is called the

• A. Trunk line
• B. Link
• C. Subscriber loop
• D. Leased line

60. What is the local loop of a telephone system?

• A. It is a two-wire or four-wire communication circuit between the customer’s premise and the central office
• B. It is a group of wires connecting a telephone set to a modern
• C. It is a four-wire circuit connecting a facsimile machine to a computer
• D. It is a single piece of wire connecting the subscriber’s telephone set to another set in an adjacent room.

61. Which of the ff. equipment is used in long loop design?

• A. Dial long lines
• B. Voice repeater
• C. Loop range extender
• D. All of the above

62. What is a two-wire circuit?

• A. A circuit usually in the subscriber loop, between the telephone set and the local central office.
• B. A circuit having only two terminals, both terminals having the same instantaneous voltage.
• C. A circuit with one input terminal, one output terminal, and a common ground.
• D. A circuit consisting of two transmission lines.

63. 1 mW is equal to

• A. 90 dBm
• B. 0 dBm
• C. -30 dBm
• D. 120 dBm

64. Which of the following responds to the request of a subscriber by sending a dial tone?

• A. Line finder
• B. First selector
• C. Connector
• D. Line equipment

65. The other name of Class 2 office in the North American Switching Plan.

• A. Primary center
• B. Section
• C. Regional center
• D. Toll points

66. A cell in the cellular telephone system means

• A. A power source
• B. Small area
• C. Large area
• D. Service area

67. What is the linking point between cell phone and regular telephone?

• A. Base station
• B. Control office
• C. C.O.
• D. MTSO

68. What is the typical power output of a cellular phone?

• A. 5 W
• B. 10 W
• C. 1 W
• D. 3 W

69. When a single cell is divided into smaller cells that process is called

• A. Cell splitting
• B. Cell division
• C. Reuse
• D. Cell sharing

70. The first cell shape is a square

• A. Square
• B. Circle
• C. Rectangle
• D. Triangle

71. In order to provide 100% coverage without overlap, cellular telephone system can use

• A. Hexagon cell shape
• B. Triangle
• C. Rectangular
• D. All of the above

72. What is the beamwidth of the reflector of the receiving antenna in the base station

• A. 20 degrees
• B. 30 degrees
• C. 50 degrees
• D. 60 degrees

73. A cellular phone operates on

• A. Half duplex
• B. Full duplex
• C. Echoplex
• D. Lincomplex

74. Cellular phones transmit in the band from

• A. 825 to 845 MHz
• B. 835 to 855 MHz
• C. 825 to 855 MHz
• D. 825 to 865 MHz

75. Cell phone receives in the band from

• A. 860 to 880 MHz
• B. 870 to 890 MHz
• C. 870 to 880 MHz
• D. 860 to 890 MHz

76. What is the frequency separation between the transmit and the receive channels?

• A. 30 MHz
• B. 45 MHz
• C. 55 MHz
• D. 40 MHz

77. For channel 1, transmit/receive frequency is

• A. 825.030/870.030 MHz
• B. 835.03/880.03 MHz
• C. 825.015/870.015 MHz
• D. 825.15/870.15 MHz

78. The number of transmit/receive channels in the cellular system is

• A. 625
• B. 645
• C. 655
• D. 666

79. The transmission range of cellular telephony is generally about

• A. 80 km
• B. 65 km
• C. 160 km
• D. 16 km

80. One of the following is not an advantage of a cellular telephone system

• A. Privacy
• B. Large service area
• C. No interference
• D. Mobility

81. When the message is transferred from one cell site transmitter to another cell site transmitter as the caller crosses a boundary __________ process takes place.

• A. Shifting
• B. Hand off
• C. Give off
• D. Turn over

82. What is the sensitivity of a cellular receiver?

• A. 20 dB
• B. 40 dB
• C. 50 dB
• D. 60 dB

83. What is the frequency deviation of the cellular telephone system?

• A. ±15 kHz
• B. ±30 kHz
• C. ±12 kHz
• D. ±75 kHz

84. Hailing channel is otherwise known as

• A. Conversation channel
• B. Calling channel
• C. Signaling channel
• D. Remote channel

85. What is an Erlang?

• A. It is a unit of magnetic field intensity measured around a conductor
• B. It is the number of erroneous bits received per unit of time
• C. It a unit of electrical energy radiated in space.
• D. It is equal to the number of simultaneous calls originated during a specific hourly period.

86. All of the cell base stations are linked together by _______ which serves as the central office and management node for the group.

• A. MTS
• B. IMTS
• C. MSTO
• D. MTSO

87. Provides interface between the mobile telephone switching office and the mobile units.

• A. Database
• B. Cell site
• C. Terrestrial link
• D. Radio transmitter

88. A phone call over the cellular network actually requires

• A. Simplex channels
• B. Half duplex channels
• C. Full duplex channels
• D. Full/full duplex

89. A method of expressing the amplitudes of complex non-periodic signals such as speech.

• A. Volume
• B. Pitch
• C. Frequency
• D. Wavelength

90. _______ is signal returned to the talker after one or more round trips between the talker and the listener.

• A. Singing
• B. Echo
• C. Jitter
• D. Crosstalk

91. ______ is a voice operated device that inserts a high loss in the opposite direction of transmission of the talking party.

• A. Hybrid
• B. 2-wire circuit
• C. Echo suppressor
• D. VNL

92. _____ is picking up of the same station at two nearby points on the receiver dial.

• A. Double spotting
• B. Hot shot
• C. Image frequency
• D. Bail shot

93. When one channel picks up the signal carried by another channel.

• A. Echo
• B. Crosstalk
• C. Party line
• D. Crosslink

94. What type of connector arrangement wherein a customer may move to another location and still retain the same telephone number.

• A. TPL
• B. Bridge
• C. TPS
• D. Party line

95. It is an advantage of sidetone.

• A. Transmission efficiency is increased
• B. Speaker increase his voice resulting in a strengthened signal
• C. No dissipation of energy in the balancing network
• D. Assures the customer that the telephone is working

96. Radio communications between points using a single share frequency.

• A. Simplex
• B. Full duplex
• C. Half-duplex
• D. Full/full duplex

97. The transmission of information from multiple sources occurring on the same facility but not as the same time.

• A. FDM
• B. TDM
• C. WDM
• D. CDM

98. When human voice and music are transmitted, the type of communication employed is known as

• A. Raditechnology
• B. Audio frequency
• C. Wired audio
• D. Radiotelephony

99. Printed documents to be transmitted by fax are converted into baseband electric signal by the process of

• A. Copying
• B. Scanning
• C. Modulation
• D. Light variation

100. What is the most commonly used light sensor in a modern fax machine?

• A. Phototube
• B. Phototransistor
• C. Liquid-crystal display
• D. Charge couple device

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Answers(51-100 SET2): 

 

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51. Unity
52. 1.5
53. C. 3
54. 4500 m
55. – 42 to -52 Vdc
56. 300 to 3400 Hz
57. Green
58. 852 & 1209 Hz
59. Subscriber loop
60. It is a two-wire or four-wire communication circuit between the customer’s premise and the central office
61. All of the above
62. A circuit usually in the subscriber loop, between the telephone set and the local central office.
63. 90 dBm
64. First selector
65. Section
66. Small area
67. MTSO
68. 3 W
69. Cell splitting
70. Circle
71. All of the above
72. 60 degrees
73. Full duplex
74. 825 to 845 MHz
75. 870 to 890 MHz
76. 45 MHz
77. 825.015/870.015 MHz
78. 666
79. 80 km
80. Large service area
81. Hand off
82. 50 dB
83. ±12 kHz
84. Calling channel
85. It is equal to the number of simultaneous calls originated during a specific hourly period.
86. MTSO
87. Cell site
88. Full duplex channels
89. Volume
90. Echo
91. Echo suppressor
92. Double spotting
93. Crosstalk
94. TPS
95. Assures the customer that the telephone is working
96. Half-duplex
97. TDM
98. Radiotelephony
99. Scanning
100. Charge couple device

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101. Which of the following is/are the main part(s) of basic cellular system.
A) A mobile Unit
B) A cell Site
C) A mobile Telephone Switching Office
D) All of the above



102. Fading of the received radio signals in a mobile communication environment occurs because of .....
A) Direct propagation
B) Multipath Propagation
C) Bi-path Propagation
D) None of the above


103.State whether True of False.
i) The cells or subdivisions of a geographical area are always hexagonal.
ii) A land to Mobile call originates through the Telephone exchange.

A) True, False

B) False, True

C) False, False

D) True, True


104. In .............. Frequency Spectrum is divided into smaller spectra and is allocated to each user.
A) TDMA
B) CDMA
C) FDMA
D) FGMA


105. In ................ multiple access is achieved by allocating different time slots for the different users.
A) TDMA
B) CDMA
C) FDMA
D) FGMA

106. State whether True of False.
i) In GSM only TDMA is used.

ii) There is zero inter-channel interference in CDMA.

A) True, False

B) False, True

C) False, False

D) True, True



107. The basic GSM is based on ____________________ traffic channels.
A) connection oriented.
B) connection less.
C) packet switching.
D) circuit switching.


108. ..................... are typically characterized by very small cells, especially in densely populated areas.
A) 2G system.
B) 3G system.
C) 2.5G system.
D) 3.5G system.


109. A antenna which attempts to direct all its energy in a particular direction is called as a .............
A) Directional Antenna
B) One to One Antenna
C) Propagation Antenna
D) Single Direction Antenna


110. Which mode is used for installing networks in wireless communication device characteristics?
A) Fixed and wired.
B) Mobile and wired. 
C) Fixed and wired. 
D) Mobile and wireless.