Convert Antenna Factor and Gain

This calculator converts Gain to Antenna Factor and vice-versa.

Antenna Factor is widely used for expressing the characteristic of an antenna used for field strength measurement. It is usually frequency dependent, so is often given in the form of a calibration table which is interpolated for intermediate values. Instruments often perform this interpolation automatically when calculating field strength from measured terminal voltage.

Electric Antenna Factor FA is the ratio of electric field strength incident upon and antenna to the loaded antenna terminal voltage, units are 1/m. It may be expressed in dB/m. There is notionally a magnetic antenna factor, but it is used much less than the electric antenna factor.

Gain of an antenna is defined (IEEE 1983) as the ratio of the radiation intensity, in a given direction, to the radiation intensity that would be obtained if the power accepted by the antenna were radiated isotropically. It may be expressed in dB (or dBi to avoid confusion with other gain references).


Frequency: (MHz)

Resistance: (Ω)

Complete one field below and hit ENTER or SPACE to calculate the other value.

Gain: (dBi)

Antenna Factor: (dB/m)



Version Date Description
1.01 29/06/13 Initial

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