f aculty of c omputer s cience & e ngineering chapter 02. radio frequency

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FACULTY OF COMPUTER SCIENCE & ENGINEERING Chapter 02. Radio Frequency

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Page 1: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

FACULTY OF

COMPUTER SCIENCE & ENGINEERING

Chapter 02. Radio Frequency

Page 2: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 1

1. When visual line of sight (LOS) is present,

RF LOS will always be present.

A. This statement is always true

B. This statement is always false

C. It depends on the configuration of the

antennas

Page 3: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 2

2. When RF LOS is present, visual LOS will

always be present.

A. This statement is always true

B. This statement is always false

C. It depends on the specific factors

Page 4: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 3

3. What unit of measurement is used to

quantify the power gain or loss of an RF

signal? Choose all that apply.

A. dBi

B. dBm

C. Watts

D. dB

Page 5: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 4

4. Using which of the following will reduce

VSWR? Choose all that apply.

A. Cables and connectors that all have an

impedance of 50 Ohms

B. Cables with a 50 Ohm impedance and

connectors with 75 Ohm impedance

C. Cables and connectors that all have an

impedance of 75 Ohms

D. Cables with 75 Ohm impedance and connectors

with 50 Ohm impedance

Page 6: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 5

5. In an RF circuit, what is the intentional

radiator defined as?

A. The output of the transmitting device

B. The output of the last connector before the

signal enters the antenna

C. The output as measured at the antenna

element

D. The output after the first length of cable

attached to the transmitting device

Page 7: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 6

6. dBi is a relative measurement of decibels

to which one of the following?

A. Internet

B. Intentional radiator

C. Isotropic radiator

D. Isotropic radio

Page 8: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 7

7. Which one of the following is considered

impedance in an RF circuit?

A. The inability to transmit RF signals

B. Interference of an RF signal during foul

weather

C. Resistance to current flow, measured in Ohms

D. The frequency on which an RF transmitter

sends signals

Page 9: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 8

8. In RF mathematics, 1 watt equals what

measurement of dBm?

A. 1

B. 3

C. 10

D. 30

E. 100

Page 10: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 9

9. Which one of the following RF behaviors is

defined as “the bending of a wave as it

passes through a medium of different

density”?

A. Diffraction

B. Reflection

C. Refraction

D. Distraction

Page 11: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 10

10. Given an access point with 100 mW of

output power connected through a 50-foot

cable with 3 dB of loss to an antenna with 10

dBi of gain, what is the EIRP at the antenna

in mW?

A. 100 mW

B. 250 mW

C. 500 mW

D. 1 W

Page 12: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 11

11. Given a wireless bridge with 200 mW of

output power connected through a 100 foot

cable with 6 dB of loss to an antenna with 9

dBi of gain, what is the EIRP at the antenna

in dBm?

A. 20 dBm

B. 26 dBm

C. 30 dBm

D. 36 dBm

Page 13: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 12

12. Given an access point with an output

power of 100 mW connected through a cable

with a loss of 2 dB to antenna with a gain of

11 dBi, what is the EIRP in mW?

A. 200 mW

B. 400 mW

C. 800 mW

D. 1 W

Page 14: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 13

13. Given an access point with an output power

of 20 dBm connected through a cable with a loss

of 6 dB to an amplifier with a 10 dB gain, then

through a cable with 3 dB of loss to an antenna

with 6 dBi of gain, what is the EIRP in dBm?

A. 18 dBm

B. 23 dBm

C. 25 dBm

D. 27 dBm

Page 15: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 14

14. What is the net gain or loss of a circuit if

it is using two cables with 3 dB loss each,

one amplifier with a 12 dB gain, 1 antenna

with 9 dBi gain, and an attenuator with a loss

of 5 dB?

A. 5 dB

B. 10 dB

C. 15 dB

D. 20 dB

Page 16: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 15

15. Which of the following is a cause of

VSWR?

A. Mismatched impedances between wireless

LAN connectors

B. Too much power being radiated from the

antenna element

C. The incorrect type of antenna used to transmit

a signal

D. Use of the incorrect RF frequency band

Page 17: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 16

16. Radio waves propagate (move) away

from the source (the antenna) in what

manner?

A. In a straight line in all directions at once within

the vertical and horizontal beamwidths

B. In circles spiraling away from the antenna

C. In spherical, concentric circles within the

horizontal beamwidth

D. Up and down across the area of coverage

Page 18: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 17

17. Why is the Fresnel Zone important to the integrity of

the RF link?

A. The Fresnel Zone defines the area of coverage in a typical

RF coverage cell

B. The Fresnel Zone must always be 100% clear of any and all

blockage for a

wireless LAN to operate properly

C. The Fresnel Zone defines an area around the LOS that can

introduce RF signal

interference if blocked

D. The Fresnel Zone does not change with the length of the RF

link

Page 19: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 18

18. The FCC allows how many watts of power

to be radiated from an antenna in a point to

multipoint wireless LAN connection using

unlicensed 2.4 GHz spread spectrum

equipment?

A. 1 watt

B. 2 watts

C. 3 watts

D. 4 watts

Page 20: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

QUESTION 19

19. In regards to gain and loss

measurements in wireless LANs, the

statement that gains and losses are additive

is:

A. Always true

B. Always false

C. Sometimes true

D. Sometimes false

E. It depends on the equipment manufacturer

Page 21: F ACULTY OF C OMPUTER S CIENCE & E NGINEERING Chapter 02. Radio Frequency

The END