21-12-2012, 05:16 PM
A Gap Coupled Stacked E-shaped Patch Antenna for Broadband Operation
[attachment=44809]
ABSTRACT
A gap-coupled stacked E-shaped patch antenna for broadband operation is proposed. The antenna is,
theoretically, analyzed using circuit theory concept. The optimized antenna shows an operational
frequency band of 207 MHz (impedance bandwidth of 40.43 % at center frequency 5.12 GHz). The
antenna operates within its acceptable limit (<-10 db return loss) with gain of 7.5 dB and 3-db-beam
width of 48.60. The theoretical results have been compared with IE3D simulated results.
INTRODUCTION
The demand for application of microstrip antenna
in various communication systems has been
increasing rapidly due to its small size, low cost,
lightweight, ease of integration with other
microwave components. But many of its
applications require wide bandwidth, which is not
provided by the conventional microstrip antenna.
Therefore, many methods have been proposed in
open technical literatures to improve the performance
of the antenna. Among these methods, cutting of
slots into the patch is a very significant advance in
improving the inherent narrow bandwidth of the
microstrip antenna [1]. By using an E-shaped patch,
Yang et al [2] has realized a broadband operation
with 30% impedance bandwidth. It may be
mentioned that the bandwidth can also be improved
by stacking a parasitic patch on the fed patch [3].
Therefore, in the present paper, an attempt has been
made to enhance impedance bandwidth of a probe
fed E- shaped patch antenna by adding a parasitic
square patch vertically above the fed patch in the
form of stacked structure.
ANTENNA DESIGN AND
FORMULATIONS
Fig. 1 shows the geometrical configuration of the
proposed antenna. The lower E-shaped patch is like a
rectangular patch of length Ld=35.6 mm and width
Wd=24.6 mm with two identical slots incorporated in
one of its radiating edge. Each slot of length LS = 15
mm and width Ws = 2.75 mm, is positioned
symmetrically with respect the feed point in such a
way that Ps = 4.5 mm. The upper square patch of side
Lp = Wp = 16 mm, is gap-coupled tothe fed E-shaped
patch. A coasial probe of diameter 1.29 mm feeds the
lower patch. Air is used as dielectric substrate of
constant εr1 = εr2 = 1 and thickness h1 = 3.55 mm, h2 =
3.75 mm for the fed and parasitic patches, respectivel
CONCLUSIONS
It is, therefore, concluded that due to dual resonance
nature the proposed antenna shows a broadband
characteristic. It is noted that the antenna operates in
acceptable limit (< -10 db return loss) from 5.10 GHz
to 7.17 GHz (frequency band of 207 MHZ) with
impedance bandwidth of 40.43 % that can be applied
in various communication systems.
[attachment=44809]
ABSTRACT
A gap-coupled stacked E-shaped patch antenna for broadband operation is proposed. The antenna is,
theoretically, analyzed using circuit theory concept. The optimized antenna shows an operational
frequency band of 207 MHz (impedance bandwidth of 40.43 % at center frequency 5.12 GHz). The
antenna operates within its acceptable limit (<-10 db return loss) with gain of 7.5 dB and 3-db-beam
width of 48.60. The theoretical results have been compared with IE3D simulated results.
INTRODUCTION
The demand for application of microstrip antenna
in various communication systems has been
increasing rapidly due to its small size, low cost,
lightweight, ease of integration with other
microwave components. But many of its
applications require wide bandwidth, which is not
provided by the conventional microstrip antenna.
Therefore, many methods have been proposed in
open technical literatures to improve the performance
of the antenna. Among these methods, cutting of
slots into the patch is a very significant advance in
improving the inherent narrow bandwidth of the
microstrip antenna [1]. By using an E-shaped patch,
Yang et al [2] has realized a broadband operation
with 30% impedance bandwidth. It may be
mentioned that the bandwidth can also be improved
by stacking a parasitic patch on the fed patch [3].
Therefore, in the present paper, an attempt has been
made to enhance impedance bandwidth of a probe
fed E- shaped patch antenna by adding a parasitic
square patch vertically above the fed patch in the
form of stacked structure.
ANTENNA DESIGN AND
FORMULATIONS
Fig. 1 shows the geometrical configuration of the
proposed antenna. The lower E-shaped patch is like a
rectangular patch of length Ld=35.6 mm and width
Wd=24.6 mm with two identical slots incorporated in
one of its radiating edge. Each slot of length LS = 15
mm and width Ws = 2.75 mm, is positioned
symmetrically with respect the feed point in such a
way that Ps = 4.5 mm. The upper square patch of side
Lp = Wp = 16 mm, is gap-coupled tothe fed E-shaped
patch. A coasial probe of diameter 1.29 mm feeds the
lower patch. Air is used as dielectric substrate of
constant εr1 = εr2 = 1 and thickness h1 = 3.55 mm, h2 =
3.75 mm for the fed and parasitic patches, respectivel
CONCLUSIONS
It is, therefore, concluded that due to dual resonance
nature the proposed antenna shows a broadband
characteristic. It is noted that the antenna operates in
acceptable limit (< -10 db return loss) from 5.10 GHz
to 7.17 GHz (frequency band of 207 MHZ) with
impedance bandwidth of 40.43 % that can be applied
in various communication systems.