HPBW
HPBW
Half-Power Beamwidth, the angular width of the main lobe of an antenna radiation pattern measured between the two directions where the power is half (-3 dB) of the peak value
Understanding HPBW
HPBW is the most common specification for antenna beamwidth, directly related to antenna gain and aperture size. Narrower HPBW indicates higher directivity and gain. For a uniformly illuminated circular aperture, HPBW is approximately 70 * lambda / D degrees.
HPBW is specified separately for E-plane and H-plane patterns, as rectangular apertures typically produce different beamwidths in each plane. The product of E-plane and H-plane beamwidths is inversely proportional to directivity.
Common Questions
Frequently Asked Questions
How is HPBW related to gain?
Gain is approximately 26,000 / (HPBW_E * HPBW_H) for a typical antenna, where beamwidths are in degrees. Narrower beamwidth means higher gain.
What determines HPBW?
HPBW is determined by the antenna aperture size relative to wavelength and the illumination taper across the aperture.
See Also