International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
Microstrip patch antenna with complimentary split
ring resonator for triple-band operation
Prashant R. T1, Vani R.M2 and Hunagund P.V3
1
Research Student, Dept. of PG Studies and Research in Applied Electronics, Gulbarga University, Gulbarga-585 106,
Karnataka, India
2
Professor & Head, University Science Instrumentation Centre, Gulbarga University, Gulbarga-585 106, Karnataka, India
3
Professor & Chairman, Dept. of PG Studies and Research in Applied Electronics, Gulbarga University,
Gulbarga-585 106, Karnataka, India
Abstract— In this paper, miniaturization of microstrip patch
antenna with triple band operation using FR4 dielectric material
is studied and presented. Microstrip antennas with compact size,
enhanced bandwidth and multiband operation by using
Metamaterial have been a candidate for the requirement in
various Wireless Communication applications. Hence, microstrip
antenna with Complimentary Split Ring Resonator (CSRR) is
designed using IE3D simulation software and measured
practically. The array of three CSRR is considered on the
ground plane and the study has been made by changing the
positions of the CSRRs. The measured results shows that
antenna with CSRRs behind the radiating patch is resonating at
three different frequencies i.e., 4.81GHz, 7.03GHz and
9.58 GHz., whereas, antenna without CSRR i.e., conventional
antenna is resonating at 5.98GHz. The size reduction of 19.56%
with return loss (RL) up to-20.65 dB (S11<-10dB) is achieved.
Along with miniaturization the antenna gives the overall
bandwidth of 13.43%. These antennas find application in
Wireless Communications.
(MTM). These Metamaterials are typically realized
artificially as composite structures that are
composed of periodic metallic patterns printed on
dielectric substrates. Metamaterials have been
extensively studied in the recent years, in the
framework of microwave applications. Several
works have been aimed towards the improvement
of the performances of antennas in the microwave
range of frequencies [4]. It is noted that some
principal properties of waves propagating in
materials with negative permittivity and negative
permeability are considered [5] and high directivity
can be obtained from conventional antenna using
Metamaterials.
The Metamaterial would include the SRR and
CSRR
has a special meaning in the field of
Keywords— microstrip patch antenna, CSRR, return loss,
microstrip antenna. Split ring resonators (SRR) are
miniaturization, bandwidth.
an integral component in realizing artificially
I. INTRODUCTION
engineered negative refractive index metamaterials.
Microstrip antennas have unique features and There electrical behavior is observed for an axial
attractive properties such as low profile, light magnetic field for which these are seldom used in
weight, compactness and conformability in microstrip configuration. On the contrary the
structure. With those advantages, the antennas can complementary split ring resonators (CSRR) are
be easily fabricated and integrated in solid-state favorable for microstrip application as it responds
devices [1-3]. Microstrip antennas are widely to axial electric field. This property has been
applied in radio frequency devices with single recently harnessed in designing planar microwave
ended signal operation. This has recently been used components [6-7]. Here in this work the CSRR
in microwave design with a combination of have been realized on the ground plane of a
metamaterials, either as a cover or a substrate. In rectangular microstrip antenna (RMSA) and the
modern wireless communication systems, the corresponding behavior have been studied using
microstrip patch antennas are commonly used in the method of moment full wave electromagnetic
wireless devices. Therefore, the miniaturization of simulation software IE3D™. In IE3D any polygon
the antenna has become an important issue in on the ground is layer treated as a slot [8]. A SRR
reducing the volume of entire communication and its complementary are illustrated in Fig. 2. The
system. V. G. Veselago in 1968 provided a complementary is the etched out portion of the SRR
theoretical report on the concept of metamaterial
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International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
in the ground plane. In this paper, the miniaturized
microstrip patch antenna with CSRRs is presented.
II. DESIGN OF ANTENNA AND CSRR STRUCTURE
Fig. 1(a) shows the geometry of the proposed
conventional microstrip antenna, where a low cost
glass epoxy dielectric material with relative
permittivity (εr) of 4.4 with thickness (h) of 1.6mm
is chosen. The conventional MSA is designed for
6GHz with dimensions L and W radiating part,
which is excited by simple 50 Ω microstrip feed
having dimensions length Lf and width Wf using
quarter wave length transformer of dimension
length Lt and Wt for their impedance matching. The
length Lg and Wg of the ground plane of the
antenna is calculated by Lg=6h+L and Wg=6h+ W
and all the dimensions are shown in table 1.
The study is carried by etching square CSRRs in
the ground plane as shown in Fig. 1(b). Initially the
array of three CSRRs are etched from the ground
plane with location of x = 0 mm along y = 3.15mm
with spacing between each CSRRs is 0.8mm which
is named as Antenna1. Next the location of CSRRs
array is x= 0 mm along y= -3.15mm which is
named as Antenna2. Finally, the Antenna 3 which
is of both the combinations of Antenna 1 and
Antenna 2 i.e., CSRRs are etched from both
locations exactly under the area of radiating patch
which is shown in Fig.1(c). By changing the
locations of CSRRs the antenna resonating
frequency is shifted towards left and the size of the
antenna is virtually reduced with multiple
resonating points. So, the final optimized Antenna
is Antenna 3 which is resonating at three different
frequency points. The parameter of the CSRR is
SL = 4mm, Sw=0.2mm g= 0.2mm and S= 1.6mm.
Fig. 2 shows the enlarged geometry of CSRR with
variables. Fig. 3(a) & 3(b) shows the photographic
view of proposed conventional microstrip antenna
and Antenna 2, Antenna3 respectively.
Fig. 1 (a)
Fig. 1(b)
Fig. 1(c)
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International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
Fig. 3 (a)
Fig. 1(d)
Fig.1 Geometry of proposed microstrip patch antenna (a) Conventional (b)
back view of antenna1 (c) back view of antenna2 and (d) back view of
antenna3
SL
Fig. 3 (b)
S
SW
g
CSRR
SRR
Fig. 2(a) A split ring resonator with design parameters (b) Complementary
split ring resonator
TABLE 1 VARIOUS DIMENSIONS OF PATCH AND GROUND
PLANE
Parameters
Length of the patch(L)
Width of the patch(W)
Length of the quarter wave
transformer(Lt)
Width of the quarter wave
transformer(Wt)
Length of the 50 Ω line(L50)
Width of the 50Ω line(W50)
Length of the ground plane (Lg)
Width of the ground plane (Wg)
ISSN: 2231-5381
Size
(mm)
11.33
15.24
4.90
Fig. 3 Photographic view of the proposed microstrip patch antenna (a)
Conventional (b) antenna 2 and antenna 3
III. RESULTS AND DISCUSSIONS
The simulation is carried out by using the mentor
graphics IE3D simulation software version 14.65.
The parameters of the proposed antennas are
measured on Vector Network Analyzer (VNA)
(Rhode and Schwarz, Germany make ZVK model
1127.8651).
Fig.4 shows the simulated return loss
characteristics of conventional microstrip antenna
and Antenna 1, Antenna 2 and Antenna 3. From this
figure it is seen that, conventional microstrip
antenna resonates at 5.91GHz and the optimized
Antenna 3 is resonating at 4.74GHz. The
impedance bandwidth over return loss less than
-10dB is determined by using the equation
0.50
6.15
3.05
40
40
Where, f1 and f2 are the lower and upper cut-off
frequencies of the band respectively, when its
return loss reaches -10dB and fC is the centre
frequency between f1 and f2.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
Conventional
Return loss (dB)
0
-10
-20
-30
Simulated
Measured
Fr 1
-40
4
5
6
7
8
Frequency (GHz)
Fig. 5 Simulated and measured return loss characteristics of conventional
MSA
Antenna 2
0
Return loss (dB)
Initially the return loss characteristic of
conventional antenna is compared with fabricated
conventional antenna and which is shown in Fig. 5.
The practically measured conventional antenna is
resonating at 5.98GHz with 250 MHz (4.18%) of
bandwidth. In the next step the CSRRs loaded
Antenna2 is measured which is resonating at three
different frequency points as Fr2= 5.24GHz,
Fr3 =6.99GHz and Fr4= 8.11GHz with bandwidths
of 107MHz, 290MHz and 300MHz respectively
with overall bandwidth of 11.07%. Finally the
optimized antenna i.e., Antenna 3 is measured
practically which also resonates at three different
frequency points as Fr5=4.81GHz, Fr6= 7.03GHz
and Fr7= 9.58GHz with bandwidths of 140MHz,
270MHz and 640MHz respectively with overall
bandwidth of 13.43%. The measured return loss
characteristics are compared with that of simulated
values and the results are shown in Table 2. Fig. 6
shows the simulated and measured return loss
characteristics of the antenna2 and Fig. 7 shows the
simulated and measured return loss characteristics
of the antenna 3. It is observed from the figures
that, all the simulated and measured results are in
good agreement with each other.
Fig. 7(a) and Fig. 7(b) show the radiation
patterns of conventional microstrip antenna and
antenna 3 at their operating bands. From these
figures it is seen that, the patterns are broadside in
nature in both the cases.
-5
-10
Fr 4
-15
Fr 3
-20
Fr 2
Simulated
Measured
-25
4
5
6
7
8
Frequency (GHz)
9
10
Fig. 6 Simulated and measured return loss characteristics of antenna 2
0
Antenna 3
Return loss (dB)
-5
-10
-15
-20
Fr 6
Fr 5
-25
Fr 7
-30
-35
Fig. 4 Return loss characteristics of proposed antennas with and without
CSRR
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Simulated
Measured
4
5
6
7
8
Frequency (GHz)
9
10
Fig. 7 Simulated and measured return loss characteristics of antenna 3
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International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
Fig. 8(b)
Fig. 8(a)
Fig. 8(a) Radiation pattern at 5.88 GHz of conventional antenna, (b) at 4.75 GHz of antenna 3
TABLE 2 COMPARED RESULTS OF SIMULATED AND MEASURED ANTENNAS
Antenna
configurations
Conventional
Antenna 1
Antenna 2
Antenna 3
Resonating
Frequency
(GHz)
Sim.
Meas.
5.90
5.98
5.15
5.15
5.24
6.81
6.99
8.11
4.74
4.81
6.93
7.03
9.42
9.58
Minimum
Reflection Coefficient(dBi)
Sim.
Meas.
-33.95
-32.21
-24
-23.92
-21.28
-19.05
-16.44
-12.76
-18.81
-20.65
-17.62
-19.69
-30.67
-24.23
Bandwidth
(MHz)
Sim.
108
107
104
138
93
117
339
Meas.
250
107
290
300
140
270
640
Bandwidth (%)
Sim.
2.99
2.07
2.02
2.03
1.96
1.68
3.59
Meas.
4.18
3.24
4.14
3.69
2.91
3.84
6.68
IV. CONCLUSIONS
ACKNOWLEDGMENT
In this work a design of triple-band metamaterial
antenna based on CSRRs has been proposed.
Because of the inclusion of CSRRs, the
conventional microstrip previously resonating at
one frequency produces three working frequencies
now. At each frequency, good matching and size
reduction is obtained. A good agreement between
simulated and measured results validates our
design. The proposed CSRRs antenna provides us a
new way to design triple-band antennas. Besides,
thanks to the presence of the CSRRs, a size
reduction and enhanced bandwidth of microstrip
antenna can be achieved.
The authors acknowledge their thanks to UGC,
New Delhi for sanctioning the IE3D simulation
software under Major Research Project, which is
most useful and reliable for designing microstrip
antennas, and DST New Delhi for sanctioning
Vector Network Analyzer for measuring the
parameters of fabricated antennas.
ISSN: 2231-5381
REFERENCES
[1]
[2]
[3]
[4]
Bahl and P. Bhartia, “Microstrip Antennas”, Dedham, Ma, Artech
house, 1981.
Constantine A. Balanis, “Antenna theory, Analysis and Design”, Third
edition, Wiley India, 2011. ISBN: 978-81-265-2422-8.
Rodney B. Waterhouse, “Microstrip Patch Antennas: A Designers
Guide”, Kluwer Academic Publishers, 2003. ISBN: 1-4020-7373-9.
Ricardo M, Ferran M and Mario S, “Metamaterials with Negative
Parameters”, Wiley 2007, ISBN:978-0-471-74582-2.
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International Journal of Engineering Trends and Technology (IJETT) – Volume 18 Number 5 – Dec 2014
[5]
[6]
[7]
[8]
D. R. Smith, Willie J. Padila, D. C. Vier, S. C. Nemat-Nasser, and S.
Schultz, “ Composite Medium wit Simultaneously Negative
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18, 1 May 2000, pp. 4184-4187.
R. Karimzadeh Baee, G. Dadashzadeh, F. Geran Kharakhili, “Using of
CSRR and its Equivalent Circuit Model in Size Reduction of
Microstrip Antenna”, proceedings of Asia-Pacific Microwave
Conference 2007, IEEE 1-4244-0749-4, 2007.
“S. R. Bhadra Choudhuri, D. R. Poddar, R. Ghatak and R. K. Mishra,
“Modulating Properties of a Microstrip Patch Antenna Using
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Zeland Mentor Graphics IE3D simulation Software version 14.65,
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as a committee member in various selection committees for
selection of Associate Professor and Professor in different
Universities.
BIOGRAPHY
Prashant R. T received his M Sc from
the department of Applied Electronics
Gulbarga University, Gulbarga in the
year 2011. He worked as a Project
Fellow in the UGC sponcerd Major
Research Project during the year 20122013. Currently he is persuing his
Ph.D in the field of Microwave Antennas from the department
of Applied Electronics, Gulbarga University, Gulbarga.
Vani R. M received her B.E. in
Electrical and Electronics from the
B.I.ET., Davanagere and M.Tech in
Industrial Electronics from S.J.C.E.,
Mysore, Karnataka. She has received
her Ph.D in Applied Electronics from
Gulbarga University, Gulbarga, India, in
year 2005. She is working as Professor
& Head, University Science Instrumentation Center, Gulbarga
University, Gulbarga. She has more than 85 research
publications in national and international reputed
journals/Conference proceedings. She presented the research
papers in National/ International conferences in India and
abroad. She has conducted several courses, workshops for the
benefits of faculties and field engineers. Her areas of interest
are microwave antennas, PC based instrumentation, embedded
controllers and Wireless communication. She has one UGC
major research project to her credit.
P. V. Hunagund received his M. Sc and
Ph. D from the Dept. of Applied
electronics,
Gulbarga
University,
Gulbarga, in the year 1982 and 1992
respectively. He is working as Professor
and Chairman of Applied Electronics
department,
Gulbarga
University,
Gulbarga. He has more than 100 research
publications in national and international reputed journals,
more than 150 research publications in international
symposium/Conferences. He has presented the research
papers in National/International conferences in India and
abroad. He has guided many Ph.D and M.Phil students. He
has three major research projects at his credit. He has worked
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