In addition to the antenna definitions, understanding descriptive antenna parameters requires a graphical and
geometric reference; that reference is provided by the spherical coordinate system as defined within Figure 1.
In the following discussion, geometric planes are
referenced with respect to the graphic of Figure 1.
Specifically, the E-plane (y-z) refers to the conditions:
f =
p/2 and -p/2 < q < p/2; while the H-plane (x-z) refers to the
conditions:
f = 0 and -p/2 < q < p/2.
The E-field and H-field of the radiated signal lie in the
respective planes. Polarization of the radiated signal is
defined with respect to the E-field.
For a microstrip antenna, radiation intensity is typically
confined to the upper half hemisphere, i.e. above the x-y
plane with radiation intensity in the positive z-direction.
MICROSTRIP ANTENNA DESCRIPTION
The microstrip, or patch, antenna is a relatively new
development which was originally patented in 1955 but did
not find broad application for almost two decades.
Construction of a microstrip antenna embodies a dielectric substrate with ground plane conductor on one side and
a thin, radiating conductor element on the opposite side as illustrated in Figure 2, where the radiating element is a
rectangular conductor attached directly to a microstrip feed line.
Figure 2 – Microstrip Antenna Construction
Figure 1 – Spherical Coordinate System
Microstrip Antenna Design
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