Jerry Martes wrote:
Can you try again to teach me how efficiency is defined??

What kind of efficiency? antenna? beam? aperture?
overall? conduction-dielectric?

Balanis defines overall antenna efficiency as the
product of:

1. reflection (mismatch) efficiency
2. conduction efficiency
3. dielectric efficiency

He gives the conduction-dielectric efficiency as:

Rr/(RL + Rr)

where Rr is the radiation resistance and
RL is the (conduction + dielectric) losses

He gives beam efficiency as:

(Beam cone power)/(Total radiated power)

He also says for a 1-dimensional aperture as a
function of taper: "The aperture efficiency is
a maximum with no taper, while the beam efficiency
is a maximum with full taper."
--
73, Cecil http://www.w5dxp.com