Chapter 4

Front 1

A plot that shows the relative signal strength around an antenna is known as what?

Back 1

Radiation Pattern

Front 2

What radiation pattern plane usually shows a top down view of the radiation pattern through the center of the antenna?

Back 2

The H Plane, also known as the Azimuth Plane

Front 3

What radiation pattern plane shows a side view of the radiation pattern?

Back 3

E Plane, also known as the Elevation Plane

Front 4

What contains concentric circles that represent relative changes in the signal strength as measured at a constant distance from the antenna?

Back 4

Polar Plot

Front 5

In a Polar Plot, what usually represents the strongest signal strength?

Back 5

The outermost circle

Front 6

In a Polar Plot, what usually represents the weaker signal strength?

Back 6

The innermost circle

Front 7

What is the measure of how effectively an antenna can focus RF energy in a certain direction?

Back 7

The Gain

Front 8

What is a measure of the antenna's focus and is normally listed in degrees for both the H and E planes?

Back 8

Beamwidth

Front 9

Beamwidth is determined by finding the strongest point on the plot, which is usually where?

Back 9

Somewhere on the outer circle.

Front 10

What are the four steps to finding the Beamwidth of an antenna?

Back 10

1. Find the strongest point

2. Decrease each direction by 3dB

3. Draw line from center to each point

4. Measure the angle

Front 11

When an alternating current is applied to an antenna, what is produced?

Back 11

An Electromagnetic Wave

Front 12

A wave has what two components?

Back 12

Electrical Field wave & Magnetic Field wave

Front 13

The wave's orientation is called the antenna _______________.

Back 13

polarization

Front 14

The antenna polarization at the transmitter must be matched to what?

Back 14

The polarization of the receiver

Front 15

The two basic types of antennas are what?

Back 15

Omnidirectional and Directional

Front 16

What type of antenna propagates a signal equally in all directions away from the antenna and is well suited for broad coverage of a large room or floor area?

Back 16

Omnidirectional antenna

Front 17

What is a common type of omnidirectional antennas?

Back 17

Dipole

Front 18

These types of antennas are often connected to wireless LAN devices that mount on the ceilings of rooms and hallways.

Back 18

Dipoles

Front 19

Most dipole antennas are between ____ and ____ inches long.

Back 19

Most dipole antennas are between 3.5 and 5.5 inches long.

Front 20

These antennas are usually less than two inches in length and contain only one short length of wire. The other segment is moved down to be used a a ground.

Back 20

Monopole Antennas

Front 21

What antennas typically have a gain of 2dBi in the 2.4-GHz band and 5dBi in the 5-GHz band?

Back 21

Integrated Omnidirectional Antennas

Front 22

What antennas produce a broad egg-shaped pattern that extends out away from the flat surface?

Back 22

Patch Antennas

Front 23

This antenna is shaped like a thick cylinder, however, it is actually made up of several parallel elements of increasing length.

Back 23

Yagi-Uda

Front 24

What antennas have a gain of about 10-14 dBi int the 2.4-GHz band?

Back 24

Yagi Antennas

Front 25

Cisco offers a 5-GHz Yagi

(TRUE/FALSE)

Back 25

FALSE

Front 26

What antenna is best for a line-of-sight wireless path that must be propagated a long distance with a single receiver location?

Back 26

The Parabolic Dish Antenna

Front 27

A parabolic dish antenna gives the antenna a gain between ___ and ___ dBi

Back 27

A parabolic dish antenna gives the antenna a gain between 20 and 30 dBi

Front 28

Beamwidth is the largest for what type of antennas?

Back 28

Omnidirectional

Front 29

Beamwidth begins to narrow through the progression of what type of antennas?

Back 29

Directional

Front 30

What antennas have the lowest gain?

Back 30

Omnidirectional

Front 31

What antennas have the highest gain as their beamwidth narrows?

Back 31

Directional

Front 32

What can you add to provide additional gain?

Back 32

an Amplifier

Front 33

What is an active, powered device that is connected inline between a transmitter and an antenna?

Back 33

Amplifier

Front 34

What is a passive device that absorbs part of the energy, inline between a transmitter and an antenna?

Back 34

Attenuator

Front 35

What device has two connectors that attach to the two ends of coaxial cable, in addition to a grounding lug?

Back 35

Lightning Arrestor

Front 36

A lightning Arrestor can never prevent the damage from a direct lightning strike.

TRUE or FALSE

Back 36

TRUE - A lightning Arrestor CANNOT prevent the damage from a direct lightning strike.