ABSTRACT
The radiation intensity is the power-per-unit solid angle in the direction and denoted by . The average radiation intensity over radi-
ans (solid angle) is the total power divided by . Hence, Eq. (10.1) can be written as
It follows that
As an approximation, it is customary to rewrite Eq. (10.3) as
GD G Ae
GD maximum radiation intensity average radiation intensity
--------------------------------------------------------------------------------=
θ φ,( ) P θ φ,( ) 4π 4π
GD 4π maximum radiated power unit solid angle⁄( )
total radiated power -------------------------------------------------------------------------------------------------------------------------------------=
GD 4π P θ φ,( )max
P θ φ,( ) θd φd
∫ ---------------------------------------=
where and are the antenna half-power (3-dB) beamwidths in either direction.