Karteikarten
04
Karten in diesem Stapel (19)
- 1What is azimuth chartH-Plane
Top-down view of the radiation pattern of an antenna - 2What is the elevation chartE-Plane
Side view of the radiation of an antenna - 3What is the beamwidthMeasures how broad or narrow the focus of an antenna is
- 4What is an omnidirectional antennaRF radiates coverage in all directions
- 5What is a semidirectional antennaRF radiates similar to a wall sconce.
Directional across a large area - 6What is a highly directional antennaRadiates RF similar to a spotlight focusing light
- 7What are sector antennasHigh gain semidirectional antennas
Providing coverage in a pie-shape
Also known as sectorized array - 8What is static beamformingDirectional antennas in a fixed radiation pattern
- 9What is dynamic beamformingFocused RF energy in a specific directional
Radiation pattern can change per frame - 10What is transmit beamformingTransmits multiple phase-shifted signals
Either implicit or explicit
Introduced in 802.11n - 11What is implicit transmit beamformingUse of implicit channel-sounding process to optimize phase differentials
- 12What is explicit transmit beamformingRequires feedback from the station to determine amount of phase-shift required for each signal
Defined in 802.11ac - 13What is the fresnel zoneArea surrounding the path of visual line of sight between two point-to-point antennas
- 14First Fresnel zoneClosest ellipsoid
- 15What is Earth bulgeFor antennas more than 7 miles away
Impedes on Fresnel zone - 16What is antenna polarizationAlignment of antenna
Should be oriented same way as the receiving antenna for strongest signal - 17What is antenna diversityHelps compensate for multipath
AP w/ two or more antennas to minimize multipath - 18MIMOMultiple-Input, Multiple-Output
Antenna diversity
Takes advantage of multipath - 19VSWRVoltage Standing Wave Ratio
Measurement of change in impedances to an AC signal
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- Beschreibung
- cwna CWNA Karteikarten am 04, erstellt von rowelld am 06/09/2015.
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- rowelld
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