The Antenna gain reference article from the English Wikipedia on 24-Apr-2004 (provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Antenna gain

Antenna gain is the sensitivity of an antenna in a particular direction, compared with the sensitivity of an isotropic antenna in any direction, or a dipole antenna in the equatorial direction. The two measurements are measured in decibels and denoted by dBi and dBd respectively.

For dish-type antennas, gain is proportional to the aperture (reflective area) and surface accuracy of the antenna, as well as the frequency being transmitted/received. In general, a larger aperture antenna has a higher gain. Also, the higher the frequency, the higher the gain. Surface inaccuracies are more of a factor at higher frequencies.

This is the "Antenna gain" reference article from the English Wikipedia. All text is available under the terms of the GNU Free Documentation License. See also our Disclaimer.