Deck 3: Radio Frequency Communications

Question 1

What type of transmission is a broadcast radio station an example of?

A) duplex
B) half-simplex
C) simplex
D) half-duplex

Answer 1

C

Question 2

Which of the following is a type of RF filter?

A) top-pass
B) mid-pass
C) bandpass
D) medipass

Answer 2

C

Question 3

TDMA was developed to overcome the problem of crosstalk.

Answer 3

True

Question 4

If a low-pass filter is set at 2200 MHz, which of the following signals would be allowed to pass through?

A) 2400 MHz
B) 1500 GHz
C) 1000 MHz
D) 23000 KHz

Question 5

Which of the following would take a transmission band of 1000 Hz and divide it into 100 channels of 10 Hz each to accommodate multiple access?

A) FDMA
B) TDMA
C) CDMA
D) SDMA

Question 6

A disadvantage of CDMA is that it can only carry one third the amount of data of TDMA.

Question 7

A high-pass filter allows all signals above a minimum threshold to pass through.

Question 8

Which of the following is NOT a common component of all radio systems?

A) filter
B) emitter
C) mixer
D) antenna

Question 9

What is the term for signals that get reflected and travel different paths between transmitter and receiver arrive out of phase?

A) electro-magnetic interference
B) reflective attenuation
C) multipath distortion
D) phase misalignment

Question 10

Objects in the path of a radio signal can cause which of the following?

A) crosstalk
B) amplification
C) EMI
D) attenuation

Question 11

What can take place when signal strength falls close to or below the level of noise?

A) SNR
B) interference
C) crosstalk
D) attenuation

Question 12

Which type of device is considered active device because it adds power to a signal?

A) mixer
B) filter
C) antenna
D) amplifier

Question 13

The sidebands of a frequency carrier are best described as which of the following?

A) the sum of the carrier signal and the highest value of the mixer output
B) the difference between the highest and lowest input frequency
C) the average of the high and low values of the input signal
D) the sum and difference of the highest input signal and carrier frequency

Question 14

What kind of signals can result from the process of modulating a signal with data to be transmitted?

A) harmonics
B) passbands
C) modulators
D) sidebands

Question 15

Which multiple access method overcomes the problem of crosstalk and divides the transmission time into several slots?

A) SDMA
B) CDMA
C) TDMA
D) FDMA

Question 16

Which multiple access method uses a spreading code?

A) CDMA
B) TDMA
C) SDMA
D) FDMA

Question 17

Which type of switching is used in a POTS system?

A) packet switching
B) circuit switching
C) cellular switching
D) frame switching

Question 18

What problem can a directional antenna reduce in severity?

A) reflective attenuation
B) multipath distortion
C) phase misalignment
D) electro-magnetic interference

Question 19

A mixer separates an input into two or more outputs.

Question 20

There are no power limits imposed on devices using the unregulated bands.

Question 21

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
transmission that occurs in only one direction

Question 22

_______________ transmission uses low-power, precisely timed pulses of energy that operate in the same frequency spectrum as low-end noise and is used in WiGig.

Question 23

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
moving a signal from one wire or frequency to another

Question 24

____________________ transmission is typically used in consumer devices such as CB radios or walkie talkies where you have to hold down a button while speaking.

Question 25

Which type of standard is an official standard controlled by and organization or body open to everyone?

A) de jure standards
B) de facto standards
C) consortia standards
D) paramount standards

Question 26

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
a switching technique in which a dedicated and direct physical connection is made between two transmitting devices

Question 27

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
transmission that occurs in both directions but only one way at a time

Question 28

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
an antenna that radiates the electromagnetic waves in one direction only

Question 29

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
unregulated radio frequency bands that are available in the United States to any users without a license

Question 30

_________________ uses direct sequence spread spectrum technology.

Question 31

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
stray oscillations that result from the process of modulating a wave and that
fall outside the range of frequencies used for transmission

Question 32

Which international standards organization coordinates global communications networks and services and is actually a treaty organization?

A) IAB
B) TIA
C) ISO
D) ITU

Question 33

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
data transmission that is broken into smaller units

Question 34

A technique called ______________ array processing replaces a traditional antenna with an array of antenna elements.

Question 35

A __________________ filter sets a range of frequencies that include a minimum and maximum threshold.

Question 36

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
transmissions in which data flows in either direction simultaneously

Question 37

Which standards organization functions as a clearinghouse for many types of standards development in the U.S.?

A) ETSI
B) IETF
C) ANSI
D) ISOC

Question 38

Which standards body deals with user-premises equipment and satellite communications?

A) IAB
B) TIA
C) IETF
D) ISCO

Question 39

In which frequency band will you find an 802.11 network?

A) medium frequency (MF)
B) super high frequency (SHF)
C) extremely high frequency (EHF)
D) very high frequency (VHF)

Question 40

MATCHING
a. circuit switching
b. directional antenna
c. full-duplex transmission
d. half-duplex transmission
e. harmonics
f. license exempt spectrum
g. packet switching
h. signal-to-noise ratio
i. simplex transmission
j. switching
the measure of signal strength relative to the background noise

Question 41

What is the purpose of a mixer? Include a discussion of sidebands in your answer.

Question 42

What are two advantages that TDMA has over FDMA?

Question 43

What advantages does packet switching have over circuit switching for transmitting data?

Question 44

What is multipath distortion?

Question 45

What are three advantages of CDMA over TDMA?

Question 46

List the three types of RF filters.

Question 47

Why are filters found in transmitters?

Question 48

Describe time division multiple access.

Question 49

What is an amplifier and why is it a crucial component in a radio system?

Question 50

What does a filter do and why is one needed in a radio system?