This is the Section 5 Module 20 of the compiled Communications Coaching Materials taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies (EST), Communications Books, Journals and other Communications References. This particular Coaching Notes in Communications Engineering has random Questions and Answers in random topics. Make sure to familiarize each questions to increase the chance of passing the ECE Board Exam.
Communications Engineering Coaching: Section 5 Module 20
1. A parabolic antenna in
which the feed
radiator is mounted at or behind the surface of the concave
downlink frequency or base station to mobile station frequency band in GSM
nominal channel spacing of time division duplexing (TDD).
the IS-95A cellular service, the base station transmit frequency is ___ above
the mobile station transmit frequency.
installation tension that can be given to a lightweight internal cable
without causing damage.
B-1 FM broadcast stations with an authorized transmitter power of 500 watts,
shall in no case have an effective radiated power lower than ____.
fiber number that has the typical color of orange in multi-core fiber cables.
installation tension that can be given to a more rugged fiber cable without
is the typical color of fiber number ___ in a multi-core fiber.
signaling path provided by a cable television system to deliver to subscriber
terminal signals that are intended for reception by equipment other than a
television broadcast receiver only when used with auxiliary equipment.
time it takes to transmit 1000 kbps graphic image via a 10 Mbps cable modem.
proprietary channel bonding equipment that can boost network up to 108 Mbps
in the Wi-Fi world.
cable television, the receiving antenna should be cut to respective channel
frequency for optimum reception with a front-to-back ratio not less than ___dB
ideal reverberation time of which is 0.8-1.2 s
should be avoided inside an acoustical room?
Long echoed voice
of the sources of errors of GPS signal is ionospheric effect which
contributes ___ of error.
+/- 5 m
first Atlantic telephone cable to use optical fiber that went into operation
placing cardiods-patterned microphones, each microphone should be at least
four times as far as from the next one as it is from the sound source. This
is known as a ___ rule.
ITU-T recommendation for data compression that was issued in 1990 and uses
the Limpel-Ziv Welch compression algorithm.
TV broadcast mainly used in Western Europe.
tape format used in video recording that has a track scanning rotation seep
of 1800 rpm.
error correction code used by digital video cassette (DVC).
composite video signal measurement, what corresponds to 0 IRE value?
composite video signal measurement, what corresponds to 100 IRE value?
equation for luminance for TV.
TV standard which tends to replace PAL/SECAM in Europe.
what channel does superband cable television starts.
aural deviation for television.
is previously known as _____, reduced carrier.
has the compression of 200:1.
microwave communications, the maximum obstruction which a microwave link can
Hamming code, there are ___ bits and ____ bits for each parity checking.
many mastergroups are there in a jumbogroup.
is done to digital bits of data due to circuitry action so as not to have an
Reduction of jitter
of radiographic contrast with grid to that without a grid.
Contrast Improvement Factor
used when there are LC.
_____ 1G Mobile phone with the Nordic Mobile Telephone (NMT) system was
"call handoff" feature was invented to allow mobile-phone users to travel
during the same conversation.
FM stereo, the maximum distance covered is significantly reduced, this is due
to the presence of the _________ kHz subcarrier modulation
Private operational fixed microwave is on the range of ________ dB.
Measurement for protocols.
Rate for the scanning of 525 lines.
As per Philippine standard, frequency allocation of AM Radio Broadcasting is
Type of AM which operates at nighttime under 250 W or off-air, field strength up
to 140 mV/m at
The coding scheme which has the easiest….
The bandwidth covered by the FM for hearing.
The most sensitive frequency for human hearing.
What type of curve does our ear for telephone used.
How many ISDN channels are there?
For a reflection of 20 dB, __% is for loss and __% is absorbed by the load.
Payment for a 1 MHz bandwidth
Paid up capital on 3G.
How many horizontal lines are blanked in TV?
Downlink (receiving) assigned to GPRS
Disadvantage of slope detection of FM
No noise discrimination
The next channel if there is accommodating the 88.1 MHz channel.
The reverberation time for clear speech.
The maximum BER for 99.97%
1 in 10 ^3
illuminating the transducer through the fiber, tungsten halogen lamps or
broadband, ____________ light emitting diodes are suitable.
legacy data rates approximately
High definition TV picture contains about __________ times as much as info as
the present NTSC TV.
IMTS2000 maximum data rate for stationary user is
The process of adjusting the orbit of a geostationary satellite so that it
appears to remain stationary above a point on the earth.
The wavelength commonly used on the modern long distance fiber communications
HDTV compare with NTSC analog.
12 to 18 dbm
microwave communication, what concepts may be used to analyze interference by
obstacles near the path of a radio beam?
In data communications, a 2400 bps modem running Class 4 would appear to
operate at ______ bps.
The full IEEE 1394b specification supports optical connections up to 100
meters in length and data rates all the way to _______ gbps.
wavelength has the minimum loss in optical fibers?
Fine for unauthorized servicing of mobile telephone.
What is the maximum power allowable for remote pick up stations used as
broadcast auxiliary services for AM and FM broadcast stations.
Absorption coefficient of a surface material to absorb sound energy.
It is an error-correcting code used for correcting transmission errors in
synchronous data streams.
Hamming in Code
Variation in signal loss.
It is often defined as the loss incurred by an electromagnetic wave as it
propagates in a straight line through a vacuum with no absorption or
reflection of energy from nearby objects.
Free Space Path Loss
Sampling of an analog signal using a sample-and-hold circuit that the sample
has the same amplitude for its whole duration.
Caused by the difference in the propagation times of light rays that take
different path down a fiber.
Acceptance Modal dispersion
Closely related to acceptance angle and is the figure of merit commonly used
to measure the magnitude of the acceptance angle.
Actual user info conveyed through the system.
A navigational technique that determines position by extrapolating a series
of measured velocity increments.
Standard that describes Ethernet-type networks is
The word “Base” in 10BaseT means
The cable carries baseband signals
The primary audio channel remained at 50Hz to 15KHz, while an additional SCA
channel is frequency translated to the _________ passband.
60 KHz to 74 KHz
The fastest output rate of change (baud) is also equal to ______ of the input
The sampling process alters the frequency spectrum and introduces an error
Signal rate of RS 232 normally used as interface between DTE and DCE.
An AM broadcast service area in which groundwave field of 1mV/m (60 dBu) is
not subjected to objectionable interference or objectionable fading.
Primary service area
BW for fiber optics.
International frequency distress for radio telephony
rate of STS-1
Telephone switch that connects only to other switches.
802.15.4 also known as
typical range of vidicon dark current
of antenna pattern so that the major lobe is at angle below the horizontal.
Ethernet system that uses a special “Thick Ethernet”
A standard classical