____________ is used by IM and other applications that provide voice services over lower-speed digital circuits.
adaptive differential pulse code modulation
Frequency modulation refers to the changing of the height of the sound wave.
T
F
False
Time (non-statistical) division multiplexing differs from frequency division multiplexing because it:
A) does not share a communication circuit
B) splits the communication circuit vertically (with time slots) instead of horizontally
C) increases the wavelength and phase angles of the baseband frequency used for transmission
D) moves the baseband of a circuit by shifting it to a higher frequency
E) reduces baseband signal velocity more than frequency division multiplexing
B) splits the communication circuit vertically (with time slots) instead of horizontally
Digital transmission produces more errors than analog transmission.
t or f
False
Digital transmission permits higher maximum transmission rates when compared to analog.
t or f
True
Multimode fiber is capable of longer transmission distances than single mode fiber.
t or f
False
_____________ can be thought of as dividing the circuit horizontally.
Frequency division multiplexing Statistical frequency division multiplexing Statistical time division multiplexing Time division multiplexing Wavelength division multiplexing
Frequency division multiplexing
Data is physically transmitted from one computer or terminal to another in the ________ layer.
physical
With modem communications, the receiving modem converts the incoming digital signal from the telephone line into an analog signal that can be understood by the computer.
T or F
F
A(n) ___________ divides one high-speed communication circuit into several lower speed circuits for the primary reason of saving communication line costs.
transponder multiplexer inverse multiplexer codec intelligent terminal
multiplexer
Which of the following is a characteristic of sound waves that can be modulated to convert digital data into analog signals?
phase attenuation bipolar bandwidth codec
phase
_____________ is not a form of modulation used to transform digital data into analog signals.
synchronous time division amplitude shift keying amplitude modulation frequency modulation phase modulation
synchronous time division
In general, networks designed to transmit primarily computer data are likely to be ________.
international level 1 numeric analog digital
digital
Which type of digital signaling would experience fewer errors because it has more distinct signals?
unipolar serial bipolar attenuation Huffman encoding signal
bipolar
A _________ is an FDM device that splits the physical circuit into three logical circuits (phone, upstream data, downstream data).
DSL modem cable modem wireless router V.44 modem Serial modem
DSL modem
The representation of the character A by the group of 8 bits, 01000001, is an example of:
digital coding phase modulation binary modulation analog transmission pitch variation
digital coding
Based on the TIA/EIA 568-B structured cabling standard, the cabling that runs from the telecommunications closet to each work area is called backbone cabling.
True or False
F
In general, older networks and local loops designed to transmit voice data are likely to be ________.
international level 2 numeric digital analog
analog
Microwave transmissions require a line of sight between any two points.
T or F
T
Which of the following statements is correct?
A) Parallel transmission is most often used for sending data on a circuit that is made up of one wire.
B) Parallel transmission is distinguished from serial transmission by the fact that the transmitting device sends a single bit, then a second bit, and so on, until all the bits are transmitted.
C) Parallel transmission is only used for analog data.
D) Serial transmission is slower than parallel transmission.
E) Parallel transmission is the same as serial transmission.
D) Serial transmission is slower than parallel transmission.
Signal bandwidth is the difference between the highest and lowest frequencies in a band.
T or F
T
Fiber optic cable can only be used on LANs.
T or F
F
______________ refers to the time it takes for a signal to travel from sender to recipient (highly exaggerated with satellite transmission).
Line-of-sight effect Multimode index Saturation effect Raindrop attenuation Propagation delay
Propagation delay
Radio data transmission requires that each device has a radio receiver/transmitter and uses a specific frequency.
T or F
T
In a multipoint circuit configuration, each computer can use the circuit at the same time.
T or F
F
Equipment used to transform analog voice signals to digital signals and digital signals to analog signals.
voice converter modem codec multiplexer demodulator
codec ?
Multitasking means to break one high-speed physical communication circuit into several lower-speed logical circuits so that different devices can simultaneously use it.
t or f
F
A(n) ___________ divides one high-speed communication circuit into several lower speed circuits for the primary reason of saving communication line costs.
transponder multiplexer inverse multiplexer codec intelligent terminal
multiplexer
A coding scheme that uses 10 bits to represent each character is capable of representing _________ different characters.
Group of answer choices
256 20 200 512 1024
1024
The medium is the physical matter or substance that carries the voice or data transmission.
True
False
T
In full-duplex transmission, two stations can send and receive simultaneously.
T or F
T
ASCII is the least popular code for data communications.
T or F
F
___________ refers to the spreading of the signal that different parts of the signal arrive at different times at the destination.
turnaround time propagation delay dispersion insulation attenuation
dispersion
Having a conversation with someone using a cellular phone is an example of _________ transmission.
simplex full-duplex half-duplex analog digital
full-duplex
______ is a modem standard that uses Lempel-Ziv encoding to compress data.
V.22 V.44 V.32bis V.34 RS 232
V.44
The type of multiplexer that divides the circuit horizontally into different light frequencies that are transmitted simultaneously across many channels is a:
wavelength division multiplexer time division multiplexer statistical time division multiplexer frequency division multiplexer statistical frequency division multiplexer
wavelength division multiplexer
Of all the media available, fiber optic provides the highest transmission speeds.
T or F
T
Two fundamentally different types of data are:
DSL and ADSL asymmetric and symmetric Microsoft and IBM digital and analog local area and wide area
digital and analog
WDM is a version of FDM used in fiber-optic cables.
T or F
T
One way to reduce quantizing errors is to increase the sampling rate of the analog signal.
T or F
T
In which type of modulation is a 1 distinguished from a 0 by shifting the direction in which the wave begins?
bandwidth modulation amplitude modulation frequency modulation phase modulation codec modulation
phase modulation
_____________ refers to the difference between the original analog data and the approximation of that data using the techniques for translating from analog data to digital signals.
Group of answer choices
quantizing error handshaking phase modulating frequency POTS anomaly amplitude Trellis effect
quantizing error
Another term for the weakening of a signal over distance is:
turnaround time propagation delay dispersion insulation attenuation
attenuation
Frequency is the number of cycles per second and is expressed in Hertz.
T or F
T
Data compression can increase the throughput of a communication link.
T or F
T
Manchester encoding is a special type of bipolar signaling in which the signal is changed from high to low or from low to high in the middle of the signal.
T or F
T
The room that contains the cable termination points and the distribution frames is referred to as
telecommunications closet equipment room building entrance backbone room work area
Telecommunications Closet
Computers produce digital data whose values are binary: 0 or 1.
T or F
T
The direction in which the sound wave begins is known as:
amplitude, which our ears detect as loudness
frequency, which our ears detect as pitch
phase
bandwidth
furlong
phase
With respect to converting digital data into analog signals, AM stands for:
Group of answer choices
Asynchronous Manchester Analog Multimode Amplitude Modulation Anomaly Multiplexing Analytical Mosaic
Amplitude Modulation
When sending four bits at a time using frequency modulation, the number of different frequency levels that would be needed would be _______.
Group of answer choices
24 16 2 8 4
16
The typical range of human hearing is:
Group of answer choices
0 to 4,000 Hz 0 to 1,200 Hz 20 to 14,000 Hz 0 to 300 Hz 0 to 56,000 Hz
20 to 14,000 Hz
One form of interference with satellite transmission is called raindrop attenuation in which the transmissions are absorbed by heavy rain.
T or F
T
____________ is a modulation technique that combines two different amplitude combinations with eight different phase combinations modulation to send four bits per symbol.
quadrature amplitude modulation time division multiplexing synchronous digital line control pulse code modulation baseband signaling
quadrature amplitude modulation
When all bits of a character are transferred one after another, the bits are transferred in ___________ mode.
serial frequency division multiplexing parallel full complex
serial