"Michael R. Davis" wrote in message
...
I'm reading an article about antenna aperature. Is it correct to state
that dipoles have a very large aperature and something like a horn
assembly used in microwaves has a tiny aperature except for wavelength for
which the horn is designed?

Just trying to get a handle on this advanced theory.

Dipole aperture is the capture area which translates an incident field, in
W/m^2, to the actual power received by the dipole. For example the aperture
for a half wave dipole is 0.13(Lambda)^2, where Lambda is the wavelength in
meters. A 40 m half wave dipole would therefore have an aperture of 52
m^2. A horn aperture, and also a parabolic dish, aperture is the physical
area of the mouth of the horn.

Regards.

Frank