In an optical fiber, the inner core is _______ the cladding.

In an optical fiber, the inner core is _______ the cladding.

a. darker than
b. denser than
c. the same density as
d. less dense than

Answer: B

________ is the set of techniques that allows the simultaneous transmission of multiple signals across a single communication link.

________ is the set of techniques that allows the simultaneous transmission of multiple signals across a single communication link.

a. Multiplexing
b. Frequency hopping
c. Compression
d. Demodulation

Answer: A

_______ are used for cellular phone, satellite, and wireless LAN communications.

_______ are used for cellular phone, satellite, and wireless LAN communications.

a. Ultraviolet Waves
b. Radio waves
c. Infrared waves
d. Microwaves

Answer: D

____ is designed to use the high bandwidth capability of fiber-optic cable.

____ is designed to use the high bandwidth capability of fiber-optic cable.

a. WDM
b. TDM
c. FDM
d. PDM

Answer: A

If we have a ______ channel, we can send more than one ______ signals simultaneously through the channel using a broadband transmission technique.

If we have a ______ channel, we can send more than one ______ signals simultaneously through the channel using a broadband transmission technique.

a. low-pass; analog
b. band-pass; analog
c. low-pass; digital
d. band-pass; digital

Answer: B

What is the bandwidth of a signal that ranges from 1 MHz to 4 MHz?

What is the bandwidth of a signal that ranges from 1 MHz to 4 MHz?

a. 3 MHz
b. 1 MHz
c. 1 KHz
d. 4 MHz

Answer: A

In _____ transmission, the frequency of the carrier signal is modulated to follow the changing voltage level (amplitude) of the data signal. The peak amplitude and phase of the carrier signal remain constant, but as the amplitude of the data signal changes, the frequency of the carrier changes correspondingly.

In _____ transmission, the frequency of the carrier signal is modulated to follow the changing voltage level (amplitude) of the data signal. The peak amplitude and phase of the carrier signal remain constant, but as the amplitude of the data signal changes, the frequency of the carrier changes correspondingly.

a. FM
b. QAM
c. AM
d. PM

Answer: A

If the baud rate is 400 for a 8-QAM (i.e., uses 8 different signal levels) signal, the bit rate is ________ bps.

If the baud rate is 400 for a 8-QAM (i.e., uses 8 different signal levels) signal, the bit rate is ________ bps.

a. 800
b. 1200
c. 400
d. 100

Answer: B

Which multiplexing technique modulates each signal to a different carrier frequency?

Which multiplexing technique modulates each signal to a different carrier frequency?

a. WDM (Wavelength Division Multiplexing)
b. TDM (Time Division Multiplexing)
c. FDM (Frequency Division Multiplexing)
d. ADM (Adaptive Delta Modulation)

Answer: C

A parabolic dish antenna is a(n) _______ antenna.

A parabolic dish antenna is a(n) _______ antenna.

a. omnidirectional
b. horn
c. unidirectional
d. bidirectional

Answer: C

______ is a digital process that allows several digital signals to share a high bandwidth link.

______ is a digital process that allows several digital signals to share a high bandwidth link. 

a. FDM Frequency Division Multiplexing)
b. PDM (Pulse Density Modulation)
c. TDM (Time Division Multiplexing)
d. WDM (Wavelength Division Multiplexing)

Answer: C

Microwaves are _________ than low-frequency radio waves.

Microwaves are _________ than low-frequency radio waves.

a. more directional
b. more propogating
c. more periodic
d. more radiating

Answer: A

Radio and microwave signals with a low-end frequency (below 2MHz) use _______ propagation.

Radio and microwave signals with a low-end frequency (below 2MHz) use _______ propagation.

a. Line-of-sight
b. Switched
c. Ground
d. Sky

Answer: C

Amplitude shift keying (ASK), Phase shift keying (PSK), frequency shift keying (FSK) and quadrature amplitude modulation (QAM) are examples of ________ conversion.

Amplitude shift keying (ASK), Phase shift keying (PSK), frequency shift keying (FSK) and quadrature amplitude modulation (QAM) are examples of ________ conversion.

a. Analog-to-Digital
b. Digital-to-Digital
c. Analog-to-Digital
d. Digital-to-Analog

Answer: D

Which of the following is not a digital-to-analog conversion?

Which of the following is not a digital-to-analog conversion?

a. Pulse Amplitude Modulation (PAM)
b. Phase Shift Keying (PSK)
c. Quadrature Amplitude Modulation (QAM)
d. Frequency Shift Keying (FSK)

Answer: A

A periodic signal completes one cycle in 0.001 second. What is the frequency?

A periodic signal completes one cycle in 0.001 second. What is the frequency? 

a. 100 Hz
b. 1 Hz
c. 1 MHz
d. 1 KHz

Answer: D

_______ signals can have an infinite number of values in a range?

_______ signals can have an infinite number of values in a range?

a. Analog
b. Binary
c. Both analog and digital
d. Digital

Answer: A

As frequency increases, the period ______?

As frequency increases, the period ______?

a. increases
b. doubles
c. decreases
d. remains the same

Answer: C

Radio waves used for conventional TV and AM/FM radios are _______.

Radio waves used for conventional TV and AM/FM radios are _______.

a. omnidirectional
b. unidirectional
c. bidirectional
d. synchronous

Answer: A

A(n) _____ medium provides a physical conduit from one device to another.

A(n) _____ medium provides a physical conduit from one device to another.

a. radiating
b. unguided
c. wireless
d. guided

Answer: D

_______ cable consists of multiple pairs of insulated copper wires twisted together?

_______ cable consists of multiple pairs of insulated copper wires twisted together? 

a. USB
b. Coaxial
c. Twisted pair
d. Fiber-Optic

Answer: C

Which of the following communication systems primarily uses guided media?

Which of the following communication systems primarily uses guided media?

a. Local telephone system
b. radio broadcasting
c. Cellular telephone system
d. Satellite communications

Answer: A

_______ is an analog multiplexing technique to combine optical signals.

_______ is an analog multiplexing technique to combine optical signals. 

a. TDM (Time Division Multiplexing)
b. FDM (Frequency Division Multiplexing)
c. WDM Wavelength Division Multiplexing
d. DMT (Discrete Multitone Transmission)

Answer: C

Baseband transmission of a digital signal is possible only if we have a ____ channel.

Baseband transmission of a digital signal is possible only if we have a ____ channel.

a. band-pass
b. narrowband
c. low-pass
d. broadband

Answer: C

Quadrature amplitude modulation (QAM) is a combination of ___________.

Quadrature amplitude modulation (QAM) is a combination of ___________.

a. pulse amplitude modualation (PAM) and phase modulation (PM)
b. pulse amplitude modulation (PAM) and frequency modulation (FM)
c. amplitude shift keying (ASK) and frequency shift keying (FSK)
d. amplitude shift keying (ASK) and Phase shift keying (PSK)

Answer: D

________ is a type of transmission impairment in which an outside source such as crosstalk corrupts a signal.

________ is a type of transmission impairment in which an outside source such as crosstalk corrupts a signal.

a. Attenuation
b. Noise
c. Distortion
d. Decibel

Answer: B

A sine wave is _______?

A sine wave is _______?

a. aperiodic and discrete
b. periodic and continuous
c. periodic and discrete
d. aperiodic and continuous

Answer: B

16QAM encodes 4 bits per Symbol. 4000/4 =

16QAM encodes 4 bits per Symbol. 4000/4 = 

Answer: 1000 baud

If the bit rate for a 16-QAM (i.e., uses 16 different signal levels) signal is 4000 bps, what is the baud rate?

If the bit rate for a 16-QAM (i.e., uses 16 different signal levels) signal is 4000 bps, what is the baud rate?

a. 400
b. 1200
c. 1000
d. 300

Answer: C