What is beam efficiency?

The energy when radiated from an antenna, is projected according to the antenna’s directivity. The direction in which an antenna radiates more power has maximum efficiency, while some of the energy is lost in side lobes. The maximum energy radiated by the beam, with minimum losses can be termed beam efficiency.

It can be defined as  “The beam efficiency states the ratio of the beam area of the main beam to the total beam area radiated.”

The mathematical expression for beam efficiency is −

ηB  =   ΩMB

           ------

            ΩA

where,

ηB is the beam efficiency.

ΩMB is the beam area of the main beam.

ΩA is the total solid beam angle (beam area).