Introduction to Wireless Networks
Module-02 Question Set
Read textbook Chapter and slides.
1. Multipath interference effects upfade and __________ .
a. Absorption
b. Excessive retransmission
c. Cross polarization
d. Frequency hopping
2. __________ defines the linear distance traveled of one complete cycle of a electromagnetic signal.
a. Trough
b. Frequency
c. Wavelength
d. crest
3. The RF signal characteristic that bens around objects is_________.
a. Refraction
b. Diffraction
c. Scattering
d. Attenuation
4. Multiple signals arriving at a receiver that are ________ will ________ the primary signal.
a. In phase , reduce
b. In phase, attenuate
c. 180 degrees out of phase, cancel
d. 180 degrees out of phase, amplify
5. As a result of downfade, a final received signal will _________than the original transmitted signal.
a. never be stronger
b. never be weaker
c. always be stronger
d. sometimes be stronger
6. Materials that will cause reflections of RF signals are _________ .
a. Trees, lakes, carpets
b. Trees, Asphalt roads, metal
c. Lakes, asphalt road, metal
d. Lakes, metal, trees
7. Multipath propagation of an RF signal can be cause by all the follow except _______.
a. Scattering
b. Refraction
c. Reflection
d. Diffraction
e. Multiplexing
8. An RF signal encountering a chain link fence will be ________.
a. Scattered
b. Refracted
c. Reflected
d. Diffracted
e. Multiplexed
9. Refraction of an RF signal can be caused by all the following except ________.
a. Smog
b. Humidity
c. Air pressure change
d. Temperature change
e. Wind
10. Free space path loss will occur at a ______ rate and will _______ to the loss caused by sources.
a. Linear, add
b. Logarithmic, add
c. Logarithmic, subtract
d. Linear, subtract
11. The time differential between a primary signal and a reflected signal arriving at the receiver is referred
as _________.
a. Delay spread
b. Multipath
c. Spread spectrum
d. Path delay
12. RF engineers use a _______ as a frequency domain tool and a ________ as a time domain tool.
a. Oscilloscope, spectrum analyzer
b. Spectroscope, oscilloscope
c. Spectrum analyzer, oscilloscope
d. Oscilloscope, spectroscope
13. When installing indoor WLAN the engineer should be most concerned about _______ and ________.
a. Drywall use, temperature changes
b. Firewall doors, and drywalls
c. The number of people in the area and firewall doors
d. The number of people in the area and drywalls
14. An RF signal going from one medium to another will bend and is referred to as _______.
a. Diffusion
b. Scattering
c. Diffraction
d. Refraction
15. An RF source that radiates a signal equally in all directions is a __________.
a. Isotropic radiator
b. Omnidirectional antenna
c. Intentional radiator
d. Nondirectional radiator
16. Using the Rule of 10’s and 3’s doubling the power corresponds to a _____ dB change and increasing
power by a factor of ten corresponds to a _____ dB change.
a. 2, 10
b. 4, 5
c. 3, 20
d. 3, 10
17. A 4 dBd antenna is equivalent to a ______ dBi antenna.
a. 6.14
b. 4.14
c. 6.41
d. 4.41
18. 26 dBm is equivalent to ________ mw.
a. 26
b. 200
c. 400
d. 226
19. The Receiver Signal Strength Indicator(RSSI) is an indication of ________ but should not be used to
compare the characteristics of WLAN cards from __________.
a. Signal strength, different readings
b. Signal strength, different vendors
c. Signal to noise, different vendors
d. Signal to noise, different tests
20. If the distance doubles and you want the same signal level at the receiver, you must increase the EIRP
signal by _______.
a. 3 dB
b. 6 dBi
c. 3 dBi
d. 6 dB
21. In typical WLAN bridge network, the greatest signal loss is due to ________.
a. Antenna loss
b. Receiver sensitivity
c. Access point output
d. Free space path loss
22. A WLAN 100 mw access point is connected to a 3 dB loss cable, and then connected to a 7 dBi antenna
produces an _______ EIRP.
a. 400 mW
b. 250 mW
c. 300 mW
d. 200 mW
23. WLAN Radio card vendors use RSSI threshold to trigger _______ and ________ .
a. Receiver sensitivity, roaming
b. Retransmission, roaming
c. Roaming, dynamic switching
d. Dynamic switching, receiver sensitivity
24. A WALN access point outputs 400 mW is connected to a -9dB cable and then to a 19 dBi antenna
producing and EIRP of
a. 2 W
b. 300 W
c. 3000 W
d. 4 W
25. All the following are relative measures of power except ________.
a. dB
b. dBi
c. dBd
d. dBm