Wireless Networking Ch 2
What is the best example of a time domain tool that could be used by an RF engineer?
Oscilloscope
When the multiple RF signals arrive at a receiver at the same time and are ______________ with the primary wave, the results can be _____________ of the primary signal.
180 degrees out of phase, cancellation
What is the frequency of an RF signal that cycles 2.4 million times per second?
2.4 MHz
Which 802.11 radio technologies are most impacted by the destructive effects of multipath? (Choose all that apply)
802.11a 802.11b 802.11g
Using knowledge of RF characteristics and behaviors, which two options should a WLAN engineer be most concerned about during an indoor site survey? (Choose all that apply)
Brick walls User density
What term is used to describe the time differential between a primary signal and a reflected signal arriving at a receiver?
Delay spread
When an RF signal bends around an object, this propagation behavior is known as what?
Diffraction
Which three properties are interrelated?
Frequency, wavelength, and the speed of light
A standard measurement of frequency is called what?
Hertz
What are some objects or materials that are common causes of reflection? (Choose all that apply)
Metal Asphalt road Lake
Which of the following statements are true about amplification? (Choose all that apply)
RF amplifiers require an outside power source Antennas are passive gain amplifiers that focus the energy of a signal in one direction Signal strength may passively increase because of multipath upfade
Which of the following statements are true about free space path loss? (Choose all that apply)
RF signals will attenuate as they travel, despite the lack of attenuation caused by obstructions Path loss occurs at a logarithmic rate
What RF behavior best describes a signal striking a medium and bending in a different direction?
Refraction
Which of these propagation behaviors can result in multipath? (Choose all that apply)
Refraction Diffraction Reflection Scattering
Which behavior can be described as an RF signal encountering a chain link fence, causing the signal to bounce into multiple directions?
Scatter
Which of the following can cause refraction of an RF signal traveling through it? (Choose all that apply)
Shift in air temperature Change in air pressure Humidity Smog
What is an example of a frequency domain tool that could be used by an RF engineer?
Spectrum Analyzer
What are some results of multipath interference? (Choose all that apply
Upfade Excessive retransmissions
What term best defines the linear distance traveled in one positive-to-negative-to-positive oscillation of an electromagnetic signal?
Wavelength
Which of the following statements are true? (Choose all that apply)
When downfade occurs, the final received signal will never be stronger than the original transmitted signal When upfade occurs, the final received signal will never be stronger than the original transmitted signal