Performance Improvement of Double-Plus Microstrip
Patch Antenna for Satellite & Radar Application
Mehek-Moutushy Rahman Moua, Abdulla Al Sumanb, Md. Rabiul Hasanc
Dept. of ETE ,Rajshahi University of Engineering & Technology, Bangladesh
[email protected]
Dept. of ETE, Rajshahi University of Engineering & Technology, Bangladesh
[email protected]
Dept. of ETE, Rajshahi University of Engineering & Technology, Bangladesh
[email protected]
Abstract: This paper represents the design & simulation of Double –plus shape microstrip
patch antenna with multi band frequencies for satellite & Radar applications. The proposed
antenna is designed on two layers, having Paraffin or Teflon substrate and another ground
plane with an area of 30mm x 40mm each. The antenna has been applied to generate
frequency band 8.71 GHz, 3.69GHz, 16.25GHz respectively. The bandwidth of the 3
frequencies band is 3.186%, 3.576% and 4.547% respectively. The return loss S11
characteristic for the band is -26.39 dB,-15.98dB,-36.09dB.
Commercial General
Electromagnetic Solver version 7 has been used to design of the proposed antenna and all
outputs have been represented for the optimum result.
Keywords: Patch antenna, GEMS, radiation pattern, return loss, substrate height.
1 INTRODUCTION
An antenna is an electrical device which converts electric power into radio waves, and vice
versa [1]. It is usually used with a radio transmitter or radio receiver. In transmission, a radio
transmitter supplies an oscillating radio frequency electric current to the antenna’s terminals,
and the antenna radiates the energy form the current as electromagnetic waves (radio waves).
The UWB communication systems use the 3.1-10.6GHz frequency band, which includes the
IEEE 802.11a frequency band (5.15-5.825) GHz. X band (8-12) GHz is used in Radar
applications including continuous-wave, pulsed, synthetic aperture Radar and phased array.
Structure of Double-plus design microstrip patch antenna have been developed in the past for
wireless applications lies frequency between (2-8) GHz. Recently, the authors investigated the
applications, for broadband with high frequency and successfully developed several antennas
suitable for satellite band operating in multiband and various military applications[2].
To prevent interference and allow for efficient use of the radio spectrum, similar services are
allocated in bands. For example, broadcasting, mobile radio or navigation devices, will be
allocated in non-overlapping ranges of frequencies. The IEEE assigned some frequency
bands. HF ,VHF, L, S, C, X, Ku, K, Ka, V,W,G& H bands are among them[3]. Many designs
of single, dual & multi band microstrip patch antennas with triangular, square and circular
using E-slots and U-slots have been reported [4-6] in the previous work. In this paper we
designed of double plus shape microstrip patch antenna with multi band frequencies which is
can be used for satellite & Radar applications.
2 ANTENNA DESIGN
This section describes the approach of designing a patch antenna using two plus technique to
adapt the structure to the desired interest operating frequency. The proposed antenna consists
of a ground plane, a printed patch and a microstrip feeding line. The most important
parameters that affect the antenna performance, such as impedance bandwidth, gain and
efficiency are described in this section. A rectangular patch antenna fundamentally resonates
at half wavelength. Using antenna design formulas we determined the total size of the patch.
Double-plus antenna has been designed with over all dimensions 30mm x 40 mm and height
of 1.2 mm. This design antenna is used for X band & Ku band of assigned IEEE frequency
bands. Multi operation of Double-plus Patch Antenna feed by transmission line is presented.
The design specifications for the proposed antenna are:
 The dielectric material selected for the design is Paraffin or Teflon.
 Dielectric constant = 2.1
 Height of substrate (h) = 1.2 mm.
Table: 1 Dimensions of the proposed antenna (Unit: mm)
L
W
𝐿1
35
7
18
𝑊1
𝐿2
𝑊2
5
18
5
The antenna is fed by 50 Ω microstrip line, through a quarter-wavelength transformer for
impedance matching. We used transmission line feeding technique which was very easy to
fabricate and simple to match by controlling the inset position and respectively simple to
model. Using the dimensions of Table 1 the final structure of our proposed antenna is given
below:
Figure- 1: Structure of Double-Plus Design.
3. SIMULATION RESULT
The proposed antenna generates multi bands at 8.71 GHz, 13.69 GHz, & 16.25 GHz with
simulated impedance bandwidth of 3.186%, 3.576% & 4.547% respectively. As show in
Fig: 2 the simulation indicates a response at 8.71 GHz with return loss = -26.39dB, -
13.69 GHz with return loss = -15.98dB and 16.25GHz with return loss = -36.09dB. A
negative value of return loss shows that this antenna had not many losses while
transmitting the signals.
Figure-2: The return loss Double-plus or modified H-shape microstrip patch antenna.
If the dielectric constant is 3.8 as quartz then impedance bandwidth is increased but
return loss is decreased. If the dielectric constant is 4.4 as FR4 then both return loss
and bandwidth are decreased. But if the dielectric constant is 2.1as Teflon or paraffin
then both return loss and bandwidth is increased. So, choosing the dielectric constant
of 2.1 will give the exact response.Figure-3 shows the simulation results of the Eshape and Double-plus shape based on the variations value of substrate dielectric
constant (𝜖𝑟 ).
Changing of dielectric constant (Er)
Figure-3: The variation of the of substrate dielectric constant (𝜖𝑟 ) on the return loss response.
Table-2: The variation of the of substrate dielectric constant (Er) on the return loss response.
Dielectric
constant (Er)
2.1
3.8
4.4
Return loss
Magnitude
8.71GHz ,13.69GHz &
16.25GHz
11.1 GHz,13.42GHz &
16.75GHz
8.35GHz,9.63GHz &
18.1GHz
-26.39 dB,-15.98 & 36.09 dB
-19.26 dB,-29.93dB &
-25.78dB
-14.44 dB,-12.31dB &
-16.15dB
In this section the variation of bandwidth due to substrate heights is measured using
three different heights (h). Initially the simulation was done with keeping substrate
height 1mm and then it is increased to 1.2 mm and 1.4 mm. While the substrate
height is changed the dielectric constant was fixed at 2.1.
Figure-4: The variation of the of substrate height (h) on the return loss response.
Table- 3: The variation of the of substrate height (h) on the return loss response.
Substrate
height(h)
1mm
1.2mm
1.4mm
Return Loss
8.704
GHz,13.77GHz &
16.25GHz
8.71 GHz ,
13.69GHz &
16.25GHz
6.576 GHz
,8.743GHz& 16.21
GHz
Magnitude
-23.45 dB,-21.23dB &
-18.05 6dB
-26.39 dB,-15.98dB &
36.09 dB
-
-17.9 dB,-16.2dB &
-20.56 dB
Fig- 4 shows the simulation results of the Double-plus shape antenna based on the
variations value of substrate height (h). It is clear from the figure that the magnitude
of return loss will increase for the values of the substrate height 1mm & 1.2mm.But if
the substrate height (h) is 1.4mm then bandwidth will increase but return loss is
decrease. So, choosing the value of substrate height of 1.2mm gives the best
response.
4. RADIATION PATTERN
The radiation patterns at the center frequencies 8.71GHz, 13.69GHz &16.25GHz are
the applications of X band & Ku band are plotted as shown Fig:6.6 (a),(b)&(c). The
3D radiation pattern at the center frequencies 8.71GHz, 13.69GHz & 16.25GHz are
plotted as shown in Fig:6.7(a),(b)&(c). Here, both E-plane and H-plane pattern are
shown for a specific center frequency.
Radiation pattern E-plane
Radiation pattern H-plane
(a) Radiation pattern E –plane & H-plane at 8.71 GHz.
Radiation pattern E-plane
Radiation pattern H-plane
(b) Radiation pattern E –plane & H-plane at 13.69 GHz.
Radiation pattern E-plane
Radiation pattern H-plane
(c) Radiation pattern E –plane & H-plane at 16.25 GHz.
Figure- 5: Radiation pattern at the center frequencies 8.71GHz, 13.95GHz & 16.25GHz.
(a) 3D radiation pattern at 8.71 GHz
(b) 3D radiation pattern at 13.69 GHz
(c) 3D radiation pattern at 16.25GHz
Figure.6: 3D Radiation pattern at the center frequencies 8.71GHz, 13.95GHz & 16.25GHz.
The below table has shown the comparison between the referred antennadesign and
the new designed antenna [10].
Referred Design
Proposed design
Return loss
Bandwidth
Return loss
Bandwidth
-20.92dB
1.26%
-26.39dB
3.18%
-19.52dB
9.46%
-15.98dB
3.57%
-11.46dB
1.84%
-36.09dB
4.54%
5 CONCLUSION
Performance analysis of Double-plus or modified H-shaped microstrip patch antenna
with multi-band characteristic has been successfully demonstrated in this thesis
paper, the simulated return loss and the radiation pattern showed well performance
for the multi-band at 8.71 GHz, 13.69GHz & 16.25GHz, the impedance bandwidths
for the multi band are 3.186%.3.576% & 4.547% respectively. The performance of
this antenna is more fruitful then the exists design which has shown in International
Journal of Advanced research in Electrical, Electronics and Instrumentation
Engineering at Vol. 2, issue 6. This antenna works in three different bands as shown
in the return loss curve which have the value of -26.39dB,-15.98dB & -36.09dB. The
antenna structure also provides as good amount of bandwidth and directivity. Using
this Double-plus or modified H-shape the antenna efficiency and radiation efficiency
which is quite good enough for Extended AM broadcasting, Satellite & Radar
applications
6. FUTURE SCOPE
In the future study we would like to look at how other types of feed network will
affect the performance of microstrip antennas as compared to the microstrip line feed.
In this design, it is not possible to improve gain so much at resonant frequencies.
Analyzing this type of the Double-plus or modified H-shape antenna we can further
improve the gain of the antenna. Therefore, the performance of the desired antenna
will be better suited for wireless, Satellite, Radar & various military applications.
References
[1] Jump up Graf, Rudolf F. (1999). Modern Dictionary of Electronics.Newnes.
p. 29. ISBN 0750698667.
[2] Howel “Microstrip Antennas,”IEEE International Symposium on Antennas and
Propagation, Williamsburg Virginia, 1972 pp. 177-180.
[3] Per IEEE Std 521-2002 Standard Letter Designations for Radar-Frequency
Bands. Reaffirmed standard of 1984; originally dates back to World War II.
[4] “E-shaped patch antennas for high-speed wireless networks,”IEEE Trans.
Antennas Propag., vol. 52, no. 12, pp. 3213–3219, Dec.2004.
[5] M. Sanad, “Double C-patch antennas having different aperture shapes,”in Proc.
IEEE Antennas and Propagation Dig., June 1995, pp.2116–2119.
[6] Deshmukh AA. “Compact broadband E-shaped microstrip antennas,” Electronics
Letters. 2005;41(18):989-90
[7] Sang-Hyuk Wi, “Wideband microstrip patch antenna with U-shaped parasitic
elements,”.Antennas and Propagation, IEEE Transactions on. 2007;55(4):1196-9.
[8] Singh D, “Small H-shaped antennas for MMIC applications,”. Antennas and
Propagation,IEEE Transactions on. 2000;48(7):1134-41.
[9] TszYm Yum, “A novel H-shaped active integrated antenna,”.Antennas and
Propagation Society International Symposium, 2003 IEEE. 2003;2:708,711 vol.2.
[10] International Journal of Advanced Research in Electrical, Electronics and
Instrumentation Engineering vol 2, Issue 6, june 2013.