Definitions for "BEAMWIDTH"
In a plane containing the direction of the maximum of a beam, the angle between the two directions in which the radiation intensity is one half the maximum value of the beam.
The angle in degrees over which a directive antenna will provide a gain within 3 dB of the value in the direction of maximum gain.
The angle or conical shape of the beam that the antenna projects. Since larger antennas have narrower beamwidths, they can pinpoint satellites in space or in dense traffic areas on the earth with more precision.
The distance between two diametrically opposed points at which the irradiance is a specified fraction of the beam's peak irradiance; most often applied to beams that are circular in cross section.