Done: Wireless Antenna

Question 1

Which antenna type should be used for a site-to-site wireless connection?

A. patch
B. dipole
C. omnidirectional
D. Yagi

Answer 1

D. Yagi

A Yagi antenna contains a dipole but also has reflectors and directors.

Question 2

In a wireless network environment, what is calculated using the numerical values of the transmitter power level, cable loss, and antenna gain?

A. SNR
B. RSSI
C. EIRP
D. dBi

Answer 2

C. EIRP

Effective Isotropic Radiated Power

The radiated (transmitted) power is rated in either dBm or W. Power that comes off an antenna is measured as effective isotropic radiated power (EIRP). EIRP is the value that regulatory agencies, such as the FCC or European Telecommunications Standards Institute (ETSI), use to determine and measure power limits in applications such as 2.4-GHz or 5-GHz wireless equipment. In order to calculate EIRP, add the transmitter power (in dBm) to the antenna gain (in dBi) and subtract any cable losses (in dB).

Question 3

Which two pieces of information are necessary to compute SNR? (Choose two.)

A. transmit power
B. noise floor
C. EIRP
D. RSSI
E. antenna gain

Answer 3

B. noise floor
D. RSSI

signal-to-noise ratio (SNR)
A measure of received signal quality, calculated as the difference between the signal’s RSSI and the noise floor. A higher SNR is preferred.

Question 4

Which type of antenna do the radiation patterns present?

A. Yagi
B. patch
C. omnidirectional
D. dipole

Answer 4

B. patch

Question 5

Refer to the exhibit.

Which type of antenna does the radiation pattern represent?

A. multidirectional
B. directional patch
C. omnidirectional
D. Yagi

Answer 5

D. Yagi

Question 6

Refer to the exhibit. Which type of antenna is shown on the radiation patterns?

A. patch
B. dipole
C. omnidirectional
D. Yagi

Answer 6

B. dipole

Question 7

Answer 7

Radiation Patterns:
A graph that shows the relative intensity of the signal strength of an antenna within its space

Gain:
The relative increase in signal strength of an antena in a given direction

Beamwidth
Measures the angle of an antenna pattern in which the relative signal strength is half-power below the maximum value

Polarization
Radiated electromagnetic waves that influence the orientation of an antenna within its electromagnetic field

Question 8

What is the wireless Received Signal Strength Indicator?

A. the value given to the strength of the wireless signal received compared to the noise level
B. the value of how strong the wireless signal is leaving the antenna using transmit power, cable loss, and antenna gain
C. the value of how much wireless signal is lost over a defined amount of distance
D. the value of how strong a wireless signal is received, measured in dBm

Answer 8

D. the value of how strong a wireless signal is received, measured in dBm

A - Signal to Noise Ratio
B - Effective Isotropic Radio Power
C - Attenuation
D - RSSI «< Correct

Question 9

When is an external antenna used inside a building?
A. only when using Mobility Express
B. only when using 2.4 GHz
C. when it provides the required coverage
D. only when using 5 GHz

Answer 9

C. when it provides the required coverage

Question 10

Using the EIRP formula, what parameter is subtracted to determine the EIRP value?
A. transmitter power
B. antenna cable loss
C. antenna gain
D. signal-to-noise ratio

Answer 10

B. antenna cable loss

Question 11

An engineer must provide wireless coverage in a square office. The engineer has only one AP and believes that it should be placed it in the middle of the room.

Which antenna type should the engineer use?

A. directional
B. polarized
C. omnidirectional
D. Yagi

Answer 11

C. omnidirectional

Question 12

What is the calculation that is used to measure the radiated power of a signal after it has gone through the radio, antenna cable, and antenna?

A. mW
B. ERIP
C. dBm
D. dBi

Answer 12

B. ERIP

EIRP (Effective Isotroppic Radiated Power)

Question 13

EIRP (Effective Isotropic Radiated Power) is the actual amount of signal leaving the antenna. It is a measurement value in db and is based on which three components? (Choose three.)

A. Transmit Power
B. RSSI
C. Cable Loss
D. Antenna Gain
E. SNR

Answer 13

A. Transmit Power
C. Cable Loss
D. Antenna Gain

Selected Answer: ACD
EIRP (Effective Isotropic Radiated Power)
EIRP (Effective Isotropic Radiated Power) is the actual amount of signal leaving the antenna and is a value measured in db and is based on 3 values:
a) Transmit Power (dBm)
b) Cable Loss (dB)
c) Antenna Gain (dBi)

Question 14

Which antenna emits this radiation pattern?

A. omnidirectional
B. RP-TNC
C. dish
D. Yagi

Answer 14

A. omnidirectional

Question 15

Which unit of measure is used to measure wireless RF SNR?

A. dBi
B. dB
C. dBm
D. mW

Answer 15

B. dB

A. dBi (decibels isotropic) - Used to measure the gain of an antenna compared to an isotropic radiator.
B. dB (decibels) - Used to measure the signal-to-noise ratio (SNR) in wireless RF communication.
C. dBm (decibel-milliwatts) - Used to measure the absolute power level of a signal relative to 1 milliwatt.
D. mW (milliwatts) - Used to measure absolute power level directly, without using a logarithmic scale like dB or dBm.

Question 16

Which type of antenna is designed to provide a 360-degree radiation pattern?

A. Yagi
B. patch
C. directional
D. omnidirectional

Answer 16

D. omnidirectional

Omnidirectional antenna radiates radio waves uniformly in all directions, providing a 360-degree coverage pattern

Question 17

What are two characteristics of a directional antenna? (Choose two.)

A. commonly used to cover large areas
B. low gain
C. provides the most focused and narrow beam-width
D. receive signals equally from all directions
E. high gain

Answer 17

C. provides the most focused and narrow beam-width
E. high gain

Question 18

Refer to the exhibit. Which type of antenna is shown on the radiation patterns?

A. patch
B. dipole
C. omnidirectional
D. Yagi

Answer 18

D. Yagi