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A compact wideband stacked patch antenna is presented for the applications of GPS systems. This antenna covers the L1, L2, and L5 GPS bands of operating frequencies 1.575, 1.227, and 1.176 GHz, respectively. High permittivity dielectric materials are used to minimize the antenna dimensions. The obtained antenna is of dimensions

In the last few years, the microstrip antennas
are the most rapidly developing antennas. These antennas have a wide
application in the fields of mobile communications, integrated systems,
satellites, and so forth. The microstrip antennas have many advantages compared
with the conventional microwave antennas which are light weight, small size,
low cost, and ease of installation. One of the most important disadvantages of
the microstrip antennas is their limited bandwidth, especially to cover a
certain band of a specific application. The present work focuses on a design of
a wideband microstrip antenna for the GPS applications [

In the present work, a compact stacked patch
antenna is obtained for covering the three GPS bands without any tuning
techniques. The antenna is fed by a microstrip feeder which is suitable to be
integrated with the planar circuits. High permittivity dielectric materials are
used to minimize the antenna dimensions. Two different dielectric substrates of 22 and 25 dielectric constants are used. The finite difference time domain [

The proposed stacked antenna is shown in
Figure

Geometry of the proposed stacked antenna (all the dimensions are in mm).

To reduce the size of the antenna, high dielectric constant materials are used as dielectric substrates. Two different cases are considered.

The two substrates are of a ceramic dielectric material of a relative permittivity equal to 22, and the upper substrate has a height equal to 1.820 mm.

The two substrates are of a dielectric material of a relative permittivity equal to 25, and the upper substrate has a height equal to 1.323 mm. This structure is more compacted than the first one.

The proposed stacked antenna is designed by using the finite difference time domain (FDTD) [

For the antenna of Case

The field distribution

The field distribution

The scattering parameters for Case

The
scattering parameters of Case

Figure

The corresponding input impedance of antenna has scattering
parameters shown in Figure

Figure

The
scattering parameters of Case

The input impedance of the second structure is
shown in Figure

The corresponding input impedance of antenna has scattering
parameters shown in Figure

Figure

The
radiation pattern of Case

A compact wideband stacked antenna is presented
to cover the tri-bands of the GPS. High permittivity dielectric materials are
used to minimize the antenna dimensions which are