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Showing posts with label Wireless Communications. Show all posts
Showing posts with label Wireless Communications. Show all posts

Monday, May 21, 2012

Wire and Wireless Communications (C7 Pastboard: Excel)

ECE Board Exam April 2001
A duration of traffic path occupancy from a call, sometimes referred to as an average duration of occupancy of one or more path from calls.
Holding time

ECE Board Exam November 2000
Frequency band where Total Access Communication System (TACS) is allocated.
935-960 MHz; 890-915 MHz

ECE Board Exam April 2000
Referred as the forward link channel of the cellular duplex system
Cell to mobile unit

ECE Board Exam November 1999
This referred to a condition in a telephone network where the calling party cannot get connected to the party being called
Blocked call

ECE Board Exam April 1999
One of the components of a basic cellular system that handles the billing activities of the network.
Mobile telephone switching office

ECE Board Exam November 1998
Refers to a continuous tone generated in a local exchange terminal through a combination of two frequencies 350 Hz and 440 Hz
Call waiting tone

ECE Board Exam April 1998
A multiple access technique used in GSM cellular system.
TDMA

ECE Board Exam November 1997
What signal-to-noise ratio is required for satisfactory telephone services?
30 dB

ECE Board Exam April 1997
What is the advantage of sidetone?
Assures that the telephone is working

ECE Board Exam November 1996
A special device circuit connecting two private branch exchanges (PBX).
Tie trunk
ECE Board Exam March 1996
The modulation system used for telegraphy is
Frequency shift keying

ECE Board Exam Board April 2001
Describe as the signal-to-noise ratio required to meet a satisfactory telephone service
30 dB

ECE Board Exam November 2000
Which of the following system uses frequency band 870-890 MHz as a transmit band of its base station?
Advanced Mobile Phone Service AMPS

ECE Board Exam April 2000
What third symbol in emission designation indicates cellular voice transmission?
E

ECE Board Exam November 1999
A term for a conventional land telephone line which is attached to the local telephone exchange by a pair of twisted copper wires.
Fixed wire

ECE Board Exam April 1999
A mobile telephone system, which used analogue cellular radio standard which was superceded by the Advanced Mobile Phone System in the US.
IMTS

ECE Board Exam November 1998
Refers to the duration occupancy period of call during its use.
Holding time

ECE Board Exam April 1998
How wide is the spectrum bandwidth of a single GSM carrier?
200 kHz

ECE Board Exam November 1997
The standard deviation of the variation in the transmission loss of a circuit should not exceed
1 dB

ECE Board Exam April 1997
One (1) Erlang is equal to ________.
36 CCS

ECE Board Exam April 2001
A type of call where cell cannot receive the supervisory audio tones in 5 seconds causing the cell site to turn the cell transceiver.
Call drop

ECE Board Exam November 2000
Telephone channel has a band-pass characteristics occupying the frequency range of ______
300 – 3400 Hz

ECE Board Exam April 2000
A digital mobile telephone system which called a European derivative of a Global System for Mobile Communication System operating at a higher frequency band.
DCS-1800

ECE Board Exam 1999
The receiving and transmission of printed materials over the telephone wires.
Facsimile

ECE Board Exam April 1999
One of the following central office switching equipment resistance limits refers to the longest subscriber loop length.
2000 ohms

ECE Board Exam April 1998
The modulation technique used by GSM cellular system
Gaussian Minimum Shift Keying

ECE Board Exam November 1997
Nominal voice channel
4 kHz

ECE Board Exam April 1997
Transmission of printed material over telephone lines
Facsimile

ECE Board Exam November 1996
What is the transmission rate of a GSM cellular system?
270 kbps

ECE Board Exam March 1996
A device to be connected across the headset in telephone receivers to reduce the effects of acoustic shock.
Two rectifiers in parallel with opposite polarities

ECE Board Exam April 2001
The signal quality of the cells 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 is referred as _________.
Hand – off

ECE Board Exam November 2000
In mobile communication such as the cellular service, the current maximum power is rated at __________
3 watts

ECE Board Exam April 2000
A special tone frequency which is transmitted by the mobile unit to cell site signaling call termination.
10 kHz

ECE Board Exam November 1999
This is the Nordic analogue mobile radio telephone system originally used in Scandinavia.
NMT

ECE Board Exam April 1999
An analogue mobile telephone system which was designed for United Kingdowm using 900 MHz frequency band.
TACS

ECE Board Exam April 1998
An interfering current in a telegraph or signaling channel due to telegraph or signaling current by another channel.
Cross fire

ECE Board Exam November 1997
What is the channel bandwidth of a standard analogue telephone system?
300 – 3400 Hz

ECE Board Exam April 1997
1 – CCS is equal to
100

ECE Board Exam March 1996
Crosstalk coupling is ___________
dBm (disturbing pair) minus dBm (disturbed pair).
the difference between readings on a cable pair with a tone and a cable pair without tone read at the far end of the cable.
signals from one circuit that get into another circuit

ECE Board Exam April 2001
Process of automatically changing frequencies as the mobile unit transfer into a different frequency zones so that the conversation can be continued in the new zone without redialing.
Hand-off

ECE Board Exam November 1996
What is the diameter of a copper wire to be used in a 16 km loop with a dc loop resistance of 100 ohms/km?


ECE Board Exam April 2001
Process of automatically changing frequencies as the mobile unit transfer into a different frequency zone so that the conversation can be continued in the new zone without redialing.
Hand-off

ECE Board Exam November 2000
A stage in cellular communication where voice channel is assigned to link up a call connection after a mobile or network originated a call.
Call completion

ECE Board Exam November 1999
How much approximate maximum power can a human voice possibly produce?
1 milliwatt

ECE Board Exam April 1999
A transmission facility connecting points 1 and 2 which is either permanent or temporary, normally voice grade facility provided by a public network provider.
Channel

ECE Board Exam April 1998
Best described as an amplifier used in radio telephony.
Class C

ECE Board Exam November 1997
Refers to the first generation of local loop system in telecommunication technology
Analogue cellular

ECE Board Exam April 1997
1 Erlang is ____________
1 TU

ECE Board Exam November 1996
Combination of modulator, channel and detector.
Discrete channel

ECE Board Exam March 1996
The local loop of the telephone system is understood to be
A two-wire or four-wire communication circuit between the customer’s premise and the central office.

ECE Board Exam November 1997
Refers to the first generation of local loop system in telecommunication technology
Analogue cellular

ECE Board Exam April 1997
_________ is used to measure speech volume
Volume unit meter

ECE Board Exam November 1996
What component in the telephone set has the primary function of interfacing the handset to the local loop?
Induction coil

ECE Board Exam March 1996
The ______ filter attenuates signals but passes frequencies below and above that band.
Band stop

ECE Board Exam November 1996
____________ is out-of-bound signaling between toll central offices (Bell System Standard)
3700 Hz

ECE Board Exam March 1996
In a telephone system, the customer’s telephone directory numbering is from 000 to 999, what is the capacity of the system?
1,000 lines

ECE Board Exam April 2001
How much signal-to-noise ratio is required to attain a satisfactory local exchange network?
35 dB

ECE Board Exam April 2000
What is the channel bandwidth of a standard analog telephone system?
300-3400 kHz

ECE Board Exam November 1996
A voice grade circuit using the PTN has an ideal passband of
0 to 4 kHz

ECE Board Exam November 1996
What kind of receiver is used in conventional telephone handset?
Electromagnetic

ECE Board Exam April 2001
In telecommunications the acronym NAM stands for
Numeric assignment module

ECE Board Exam November 2000
Referred as the reverse link channel of the cellular duplex system.
Mobile unit to cell

ECE Board Exam April 2000
Provides interface between the mobile telephone switching office and the mobile units
Cell site

ECE Board Exam November 1996
What is the power loss of a telephone hybrid?
3 Db

ECE Board Exam April 2001
This is small radio transceiver communication device which is normally wall mounted and where the WLL subscriber plugs its telephone handset.
Telephone wireless terminal

ECE Board Exam April 2000
A term used in wireless telegraphy and telephony to counter irregular disturbing radiation due to various causes which is produced by arc transmitter causing a rushing sound in receiving telephones.
Mush

ECE Board Exam November 1996
What is the phase delay of an 800 Hz voice signal if the phase shift is 15 deg.?


ECE Board Exam November 1996
A digital identification associated with a cellular system
SIM

ECE Board Exam April 2001
Component of a basic cellular system that provides interface between the switching office and the mobile units.
Cell site

ECE Board Exam November 2000
Which of the following cellular system is the only system allowed inside United States?
AMPS

ECE Board Exam April 2000
Which of the following system uses frequency band 825 – 845 MHz as a receive band of it base station?
Advanced Mobile Phone Services (AMPS)

Tuesday, February 1, 2011

Paging and Wireless Data Networking (Blake C23)


         TRUE/FALSE

  1.   Traditional paging systems use low-power transmitters.

ANS:   F

  2.   Traditional paging systems use widely spaced transmitters.

ANS:   T

  3.   Pagers use the VHF band.

ANS:   T

  4.   Pagers use the UHF band.

ANS:   T

  5.   Pager messages typically require a lot of bandwidth.

ANS:   F

  6.   Each pager has a unique address.

ANS:   T

  7.   Typically, pager systems keep track of each pager's location.

ANS:   F

  8.   Satellite systems are used by pagers.

ANS:   T

  9.   All pagers are one-way only.

ANS:   F

10.   Wireless LANs are typically slower than wired LANs.

ANS:   T

11.   Wireless LANs are typically more expensive than wired LANs.

ANS:   T

12.   The IEEE 802.33 covers wireless LANs.

ANS:   F

13.   Few companies actually use the IEEE 802 wireless LAN specifications.

ANS:   F

14.   Wireless LANs typically use a spread-spectrum modulation.

ANS:   T

15.   IEEE 802 allows up to 1 watt of transmitter power.

ANS:   T

16.   The typical range of a wireless LAN in an office environment is about 10 meters.

ANS:   F

17.   The range of a Bluetooth system in an office environment is about 0.01 meters to 10 meters.

ANS:   T

18.   Any Bluetooth device should be able to communicate with any other Bluetooth device.

ANS:   T

19.   Bluetooth has a channel bit rate of 100 Mbps.

ANS:   F

20.   Bluetooth devices communicate automatically once they are in range of each other.

ANS:   T

21.   Bluetooth uses spread-spectrum modulation.

ANS:   T

22.   Bluetooth uses frequency hopping.

ANS:   T

23.   Bluetooth is designed for audio as well as data.

ANS:   T

24.   Currently, no wireless LAN uses light-wave transmission.

ANS:   F

25.   A wireless LAN based on light waves would need direct line of sight for connections.

ANS:   F

         MULTIPLE CHOICE

  1.   Pagers use:
a.
the VHF band only
b.
the UHF band only
c.
both the VHF and UHF bands
d.
the VHF band, the UHF band, and the ISM band


ANS:   C

  2.   ISM stands for:
a.
IEEE Standard Message
c.
Industrial, Scientific, and Messaging
b.
IEEE Secure Message
d.
Industrial, Scientific, and Medical


ANS:   D

  3.   CAPCODE is:
a.
an encryption scheme used for pagers
b.
an addressing scheme used for pagers
c.
an error-detection scheme used for pagers
d.
a digital modulation scheme used for pagers


ANS:   B

  4.   In a one-way pager system:
a.
all pages are sent from all transmitters
b.
each transmitting antenna covers a wide area
c.
transmitters use relatively high power
d.
all of the above


ANS:   D

  5.   POCSAG stands for:
a.
Pager Operations Common Standards Advisory Group
b.
Pager Operations Code Standardization Advisory Group
c.
Post Office Code Standardization Advisory Group
d.
Post Office Common Standards Advisory Group


ANS:   C

  6.   A typical pager system does not:
a.
require "handoffs"
c.
require error detection
b.
allow "roaming"
d.
all of the above


ANS:   A

  7.   The IEEE specification covering wireless LANs is:
a.
802.10
c.
802.12
b.
802.11
d.
802.13


ANS:   B

  8.   The IEEE 802 spec for wireless LANs uses the:
a.
VHF band
c.
ISM band
b.
UHF band
d.
infrared band


ANS:   C

  9.   The IEEE 802 document for wireless LANs specifies the use of:
a.
CSMA/CA
c.
CDMA
b.
CSMA/CD
d.
all of the above


ANS:   A

10.   BSS stands for:
a.
Basic Service Set
c.
Bluetooth Service System
b.
Basic Service System
d.
none of the above


ANS:   A

11.   Bluetooth uses:
a.
CDMA
c.
QPSK
b.
frequency hopping
d.
all of the above


ANS:   B

12.   Bluetooth uses the:
a.
VHF band
c.
ISM band
b.
UHF band
d.
infrared band


ANS:   C

13.   TDD stands for:
a.
Time-Division Duplex
c.
Time Delay Difference
b.
Time-Delayed Duplex
d.
Total Distance Delay


ANS:   A

14.   A Bluetooth "piconet" has:
a.
2 nodes
c.
2 to 8 nodes
b.
2 to 4 nodes
d.
2 to 16 nodes


ANS:   C

15.   Two or more connected piconets forms a:
a.
micronet
c.
TDD net
b.
multinet
d.
scatternet


ANS:   D

16.   The basic range of a Bluetooth device is:
a.
10 cm to 1 meter
c.
10 cm to 100 meters
b.
10 cm to 10 meters
d.
within 10 feet


ANS:   B

17.   IRDA stands for:
a.
Infrared Data Association
c.
Infrared Restricted Data Area
b.
Infrared Digital Association
d.
Infrared Roaming Data Area


ANS:   A

18.   The range of an IRDA system is:
a.
1 meter
c.
1 foot
b.
10 meters
d.
10 feet


ANS:   A

19.   Infrared networks:
a.
cannot penetrate walls
c.
can use reflected infrared beams
b.
can use diffused infrared beams
d.
all of the above


ANS:   D

20.   The maximum range of a typical wireless modem is:
a.
1 meter
c.
several hundred meters
b.
several meters
d.
several thousand meters.


ANS:   D

         COMPLETION

  1.   Each pager has a unique address called a ____________________.

ANS:   capcode                   

  2.   Many pagers can share a frequency using ____________________.

ANS:   TDMA                     

  3.   The POCSAG was devised by the British ____________________ Office.

ANS:   Post                          

  4.   A POCSAG message uses a ____________________-bit error correction code.

ANS:   10                            

  5.   IEEE ____________________ covers wireless LANs.

ANS:   802.11                     

  6.   The IEEE document specifies a maximum power of ____________________ for wireless LANs.

ANS:   1 watt                       

  7.   Bluetooth uses the ____________________ band.

ANS:   ISM                          

  8.   A network of 2 to 8 Bluetooth devices is called a ____________________.

ANS:   piconet                     

  9.   A Bluetooth scatternet consists of 2 or more ____________________.

ANS:   piconets                   

10.   An IRDA system is deliberately restricted to a range of ____________________.

ANS:   1 meter