Radio Frequency Technologies

Front 1

A level of desired signal above the minimum required signal for successful communication.

Back 1

Fade Margin / System Operating Margin (SOM)

Front 2

What organization creates standards for networking communications?

Back 2

IEEE

Front 3

Which organization is responsible for interoperability testing of 802.11 equipment?

Back 3

Wi-Fi Alliance

Front 4

What properties of the RF signal can be used for modulation?

Back 4

Frequency, amplitude, phase

Front 5

The distance between the beginning and the end of a single cycle of an RF signal is known as what RF characteristic?

Back 5

Wavelength

Front 6

Which RF property defines the number of times a signal oscillate in 1 second

Back 6

Frequency

Front 7

What term describes the signal strength of an RF signal?

Back 7

Amplitude

Front 8

What term describe the loss of RF signal strength?

Back 8

Attenuation

Front 9

What term describes the relationship between two or more signals that share the same frequency?

Back 9

Phase

Front 10

What term describes the movement of radio waves away from a transmitting antenna?

Back 10

Propagation

Front 11

What propagation behavior causes attenuation as the RF signal passes through a medium?

Back 11

Absorption

Front 12

What propagation behavior causes when an RF signal bounces off a medium into another direction ?

Back 12

Reflection

Front 13

What propagation behavior is occurring when an RF signal bends in another direction as it passes through a physical medium?

Back 13

Refraction

Front 14

What propagation behavior is occurring when an RF signal bounces off a medium into multiple directions?

Back 14

Scattering

Front 15

When an RF signal encounters smog, which type of RF propagation behavior can occur?

Back 15

Refraction, scattering

Front 16

When an RF signal encounters a large body of water at a sharp angle which type of RF propagation behavior can occur?

Back 16

Reflection

Front 17

When an RF signal passes through changes in air temperature, air pressure, or water vapor, which type of RF propagation behavior can occur?

Back 17

Refraction

Front 18

What term describes background noise in an RF environment?

Back 18

Noise floor

Front 19

Intersymbol interference is a result of ____

Back 19

Multipath

Front 20

When an antenna receives RF signals, the time differential between the main signal and a reflected signal is known as what?

Back 20

delay spread

Front 21

What are the four possible results of multipath?

Back 21

Upfade, downfade, Nulling and Data corruption

Front 22

What are the two types of gain?

Back 22

Passive gain and Active gain

Front 23

Name the most common device that create passive gain.

Back 23

Antenna

Front 24

What is the passive gain of antenna typically compared to?

Back 24

An isotropic radiator

Front 25

What RF component is responsible for generating the AC signal

Back 25

The transmitter generates the AC signal and modified it by using a modulation scheme to encode the data into the signal.

Front 26

The highest RF signal strength that is transmitted from an antenna is known as what?

Back 26

Equivalent isotropically radiated power (EIRP)

Front 27

WLAN vendors use RSSI thresholds to trigger which radio card behaviors?

Back 27

Roaming and Dynamic rate switching

Front 28

Which value should not be used to compare wireless network cards manufactured by different WLAN vendor?

Back 28

RSSI (Received Signal Strength Indicator)

Front 29

What type of antennas are most likely used to compensate for high wind load effect in a long-distance point-to-point bridge link?

Back 29

Grid antenna and parabolic dish

Front 30

All the components of system including a transmitter, cabling and amplifier up to but not including the antenna is known as the ____

Back 30

Intentional Radiator (IR)

Front 31

Name some absolute measurements of power

Back 31

Watt, mWatt, dBm

Front 32

Which absolute RF measurement of power reference decibels to 1 mW?

Back 32

dBm

Front 33

Which relative measurement of power is referenced to an isotropic radiator?

Back 33

dBi

Front 34

Which relative measurement of power is referenced to a dipole antenna?

Back 34

dBd

Front 35

How much will absolute power increase with +3 dB of gain?

Back 35

Double

Front 36

How much will absolute power increase with +10 dB of gain?

Back 36

10 times

Front 37

What are the three major types of antennas?

Back 37

Omnidirectional, semidirectional and highly directional

Front 38

What are the two types of omnidirectional antennas?

Back 38

Low gain and high gain

Front 39

What are the three possible results of VSWR?

Back 39

Decreased amplitude, erratic signal strength and transmitter fail

Front 40

What are the major types of semidirectional antennas?

Back 40

Yagi, planar(panel and patch) and sector

Front 41

How much of the Fresnel zone must be clear for reliable communications in an outdoor PtP bridge link?

Back 41

60%

Front 42

When a long-distance PtP link is installed, earth bulge should be considered beyond what distance?

Back 42

7 miles

Front 43

What term describes the process of two antennas sampling the received signal, looking for the best signal?

Back 43

Antenna Diversity

Front 44

What term describes the forward loss of power due to reflected voltage?

Back 44

Return loss

Front 45

What is a standard unit of measurement of electrical resistance?

Back 45

Ohm

Front 46

What is a common mounting fastener used when installing antennas?

Back 46

U bolt

Front 47

what is needed to connect a standard connector to a proprietary connector?

Back 47

Pigtail cable or connector series adapter

Front 48

True or false: Lighting arrestors will protect equipment from direct lightning strikes

Back 48

False

Front 49

Name a situation where a splitter might be used

Back 49

Although not recommended, a splitter may be used with a sectorized antennas array in point to multipoint bridge base station.

Front 50

The size of Fresnel Zone is controlled by what factors?

Back 50

Distance and Frequency

Front 51

The ratio between the maximum peak voltage and minimum voltage on a line is known as what?

Back 51

VSWR

Front 52

Amplifiers can be purchased with which of the following features?

Back 52

Bidirectional and Unidirectional amplification, Fixed gain, Fixed output

Front 53

Lighting arrestors will defend against which of the following?

Back 53

Transient currents

Front 54

What is the difference in decibels between the received signal and the background noise known as?

Back 54

Signal to noise ratio SNR

Front 55

What law states that the change in power is equal to 1 divided by the square of the change in distance?

Back 55

Inverse square law

Front 56

What is the received signal strength known as?

Back 56

received amplitude

Front 57

An electromagnetic signal with a smaller wavelength will attenuate_____ than a large wavelength.

Back 57

Faster