Impedances of a Cubical Quad Antenna
Abstract
Rectangular loop antennas and short electric dipoles
are two of the oldest antennas in existence. In 1888,
twenty years after Maxwell invented his famous Maxwell's equations,
Hertz used these two antennas to prove that
high frequency electric energy sources could radiate electro-
magnetic waves.
The "Cubical Quad" or, simply, "Quad" antenna is a
development of the rectangular loop antenna. It consists
of a pair of square loops, one-quarter wavelength on a
side or one wavelength around the periphery; one loop
being driven and the other used as a parasitic reflector.
The separation between the two is usually of the order of
0.15 to 0.2 wavelength, with the planes of the loops parallel.
While studying the properties of this antenna, it
was discovered that little had been done to develop it
from a theoretical aspect. The purpose of this thesis is
to obtain values of the self and mutual impedances existing
in such an antenna array. The values are obtained from mathematical
analysis and experimental measurements and may be
used in field pattern and gain calculations.