Subject: ANTENNA GAIN CHART This is a chart to help you determine antenna gain based on the number of elements. ------------------------------------------------------------------------- Antenna Type Decibel gain Decibel gain over isotropic over half-wave radiator dipole antenna DBi DBd ------------------------------------------------------------------------- Isotropic radiator 0 -2.1 Ground plane +0.3 -1.8 Half wave dipole +2.1 0 5/8 wave +3.3 +1.2 quad loop element +4.1 +2.0 2 element yagi beam +7.1 +5.0 3 element yagi beam +10.0 +8.0 4 element yagi beam +12.1 +10.0 2 element quad beam +9.1 +7.0 3 element quad beam +12.1 +10.0 4 element quad beam +14.1 +12.0 ------------------------------------------------------------------------- When an antenna is designed, the laws of physics have to be observed. Over the years, some antenna manufacturers have inflated their gain figures to the point that QST no longer allows gain figures to be published in antenna ads. Hopefully, this chart will clear up some misconceptions about antenna gain.