The terminology for characteristics of antennas is listed here:
- RF lobes - Shape of the RF patterns
- Beamwidth - Horizontal/Azimuth and vertical/elevation measurement angels
- Gain - Changing the RF coverage pattern
- Polarization - Horizontal or vertical
RF lobes
In radio frequency technology term, lobe refers to the shape of the RF energy emitted from an antenna element. RF lobes are determined by the physical design of the antenna. Antenna design also determines how the lobes project from an antenna element. Antennas may project many lobes of RF signal. The type of antenna utilized - omnidirectional, semi directional, or highly directional parabolic dish will determine the usable lobes. The following picture shows highly directional parabolic antenna.
Above pictures from CWAP
Beamwidth
The patterns of energy emitted from an antenna are known as lobes. For antennas, the beamwidth is the angle of measurement of the main RF lobe measured at the half-power or -3 db point. Beamwidth is measured both horizontally and vertically, in degrees.
Azimuth and elevation charts available from the antenna manufacturer will show the beamwidth angles. The azimuth is the view from above or the bird's eye view of the RF pattern. The elevation as a side view, if you were to look at a mountain form the side view.
Azimuth and elevation charts available from the antenna manufacturer will show the beamwidth angles. The azimuth is the view from above or the bird's eye view of the RF pattern. The elevation as a side view, if you were to look at a mountain form the side view.
Above pictures from CWAP
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