International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
Corner slit Rectangular patch antenna for L1 band
Miss Madhuri Gaharwal1,Prof. Ram Naresh Pal 2, Mrs. Poornima Pai3
1
PG Student TIT(Excellence) Bhopal, RGPV University. Bhopal
2
Assistant Professor, TIT (Excellence) RGPV University, Bhopal
3.
Lecturer, RVIOT Kharghar Mumbai.
ABSTRACT
In this paper a rectangular patch antenna with corner slit is discussed and compared with conventional patch antenna of
dimensions (80mm X 60mm) for GPS application. The structure is a simple patch antenna of substrate FR4. The impedance
matching and radiation characteristics of the designed structure are investigated with the aid of HFSS software. The
simulation results show that the antenna offers excellent performance for frequency 1.5455GHz. The slitting techniques
enhances the axial ratio as well as VSWR of the proposed antenna..
Keywords: GPS, Corner slit, rectangular patch antenna
1. INTRODUCTION
The modern wireless communications system requires low profile, light weight, high gain, and simple structure
antenna to assure reliability, mobility and high efficiency characteristics. Micro strip antenna satisfies such
requirements. The key features of a microstrip antenna are relative ease of construction, light weight, low cost and
either conformability to the mounting surface or, an extremely thin protrusion from the surface. This antenna provides
all of the advantages of printed circuit technology [2]. There are varieties of patch structures available but the
rectangular, circular and triangular shapes are most frequently used. In these requirements, these devices become
smaller in size and hence the antenna required for transmit and receive signals has as to be smaller and light in weight.
[5]A microstrip patch antenna consists of radiating patch on one side. The patch is generally made of conducting
material such as copper and gold. The radiating patch and feedline are usually photo etched on dielectric substrate [1].
Micro strip antennas are the first choice for these high frequency bands due to its lightweight, low cost and robustness.
The most commonly used patch structures are rectangular and circular. For rectangular patch elements there are two
degrees of freedom.
All GPS signal are in L band of frequency spectrum because L band waves penetrates cloud, fog, rain, strum and
vegetations .based on this consideration the choice of L band frequency proved to be advantageous . Each GPS satellite
transmits three carrier signals in microwave range of electromagnetic spectrum given by L1, L2 and L5. The L1 band
frequency ranges from 1.52 to 1.575 GHz.
In this paper, the design of a rectangular patch antenna with cross slit is presented and is expected to operate with
1.5244 GHz frequency. This antenna is designed on a double side fiber Reinforced (FR-4) epoxy and its performance
characteristics which include return loss, VSWR ,Axial ratio and directivity.
2. ANTENNA DESIGNING AND SIMULATION
In this paper novel geometry is proposed and simulated results are compared with conventional patch antenna results.
The geometry was simulated using HFSS. HFSS is a high performance full wave electromagnetic (EM) field simulator
for arbitrary 3D volumetric passive device modeling that takes advantage of the familiar Microsoft Windows graphical
user interface. [3]
Hear conventional rectangular microstrip patch antenna is considered as a reference antenna. The result of the
reference antenna is compared with a simulated new proposed antenna. The geometry of the proposed antenna using
FR4 as the dielectric constant εr = 4.4. thickness of the substrate h=1.59 mm. the rectangular patch has length and
width 60mm X 80mm.a coaxial probe is used to connect the microstrip path at coordinates. The antenna parameters
can be calculated by transmission lie method.
Step 1: Calculation of the width of Patch (W) .. [4]
The width of the Microstrip patch antenna is given as
Volume 4, Issue 3, March 2015
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International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
For c=3*10^8 m/s2, f o=1.57GHz, ε r=4.4
We get
W=58mm.
Step 2: Calculation of effective dielectric constFringing makes the microstrip line look wider electrically compared to its physical dimensions. Since some of the
waves travel in the substrate and some in air, an effective dielectric constant is introduced, given as:
For εr=4.4, h=1.6mm, W=58mm
We get εreff=3.99
Step 3: Calculation of Length of Patch (L)The effective length due to fringing is given as:
For c=3*10^11 mm/s, εreff=3.99, f o=1.6GHz
We get Leff =45 mm
Due to fringing the dimension of the patch as increased by ΔL on both the sides, given by:
For W=36.4mm, h, =1.53mm, εreff=3.99
We get ΔL=0.70mm
Hence the length the of the patch is: L= Leff-2ΔL=45 mm
Step 5: Calculation of Substrate dimensionFor this design this substrate dimension would be
Ls=L+2*6h Ls = 2*6h + L = 2*6(1.6) + 39 = 80mm
Ws=W+2*6h Ws = 2*6h + W = 2*6(1.6) + 30 = 80 mm
Step 6: Calculation of feed pointFor this feed would be given L/4 distance. i.e. 11mm.
Figure 1: Rectangular microstrip antenna
Simulation Results
The antenna was simulated and reference patch obtained is shown in fig.1. The return loss of antenna obtained is 12.9738 dB at 1.527 GHz.
Volume 4, Issue 3, March 2015
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International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
Fig2: s 11 parameter of reference antenn
Fig3: VSWR of reference antenna
Fig 4: Radiation pattern of reference antenna
Fig 5: Directivity of reference antenna
Fig 6: Axial Ratio of reference antenna
For the operational frequency of 1.52 Ghz the reference antenna has VSWR nearly 1.5792 and return loss bandwidth
up to -12.9738 dB has been obtained. The bandwidth obtained from the return loss with signifies 30 MHz
Volume 4, Issue 3, March 2015
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International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
Proposed antenna and simulation:
Fig 8: Radiation pattern of proposed antenna
Fig 7: Proposed antenna
The proposed rectangular patch antenna with corner slit uses diagonal feed technique. The diagonal feeding is required
to allow both the modes to be exited with single feed. The feed is located at line of the corner of the rectangle as shown
in fig.7 the proposed antenna with the feed location provide minimal axial ration as compared to the rectangular patch
antenna.
.
Fig 9: s 11 parameter of proposed antenna
Fig 11: current distribution
Volume 4, Issue 3, March 2015
Fig 10 : VSWR of proposed antenna
Fig 12 : Axial Ratio of reference antenna
Page 169
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
Table 1: Comparison table between performance of reference and proposed antenna geometry
SR.NO
ANTENNA
FREQ
RETURN
LOSS(DB)
VSWR
BANDWIDT
DIRECTIVIT
H
AXIAL
RATIO
(MHZ)
(DB)
(DB)
Y
(GHZ)
1.
REFERENCE
1.52
-12.97
1.57
30
8.60
2.30
1.54
-15.04
1.43
35
1.37
2.30
ANTENNA
2.
PROPOSED
ANTENNA
3. CONCLUSION
The radiation performance of the rectangular patch antenna with corner slit is investigated and compared with
conventional patch antenna excited under similar condition. The modified rectangular patch antenna has much
improved bandwidth, VSWR and axial ratio. The proposed antenna produces table radiation pattern within the
frequency range and exhibit good impedance matching at center frequency 1.54 GHz. The diagonal feed technique used
for the design makes this antenna a good choice in GPS application.
ACKNOWELDGMENT
I would like to thank Hon. Mr. Ram Naresh Pal for his valuable suggestions and encouragement. I am also grateful for
their valuable guidance and support. I am deeply indebted to my Head of the Department of Electronics and
Telecommunication.
REFERENCES
[1] Constantine A. Balanis,”Antenna Theory Analysis and Design,” Third Edition, Wiley Publication.Amitkumar F
Sonar, Nitesh S Mishra, Rahul P Mishra, Jayesh Mhaskar and Shilpa Kharche, “UWB Circular Monopole
Antenna”, ITSI Transactions on Electrical and Electronics Engineering, Vol. 1, no. 1, (2013), pp. 43-46.
[2] Rampal Kushwaha1, Prof. Kanchan Cecil2 1,2Department of Electronics and Telecommunication Jabalpur
Engineering College, Jabalpur, India “ Design and analysis of gain for rectangular microstrip patch antenna using
symmetrical cuts”, International Journal of Advance Technology & Engineering Research (IJATER). Vol. 1, Issue
1, November 2011
[3] Dr. Otman El Mrabet IETR, UMR CNRS 6164, INSA, 20 avenue Butte des Coësmes 35043 Rennes, FRANCE O.
El Mrabet & M. Essaadi 2005 - 2006
[4] G. Kumar and K. P. Ray, Broadband Microstrip Antennas,Artech House, Norwood, Mass, USA, 2003.
[5] Mrs. Poornima Pai, Prof. Gahankari 2Department of Electronics and Telecommunication Saraswati Engineering
College, Mumbai, India “Compact Cross spoke shaped monopole antenna”, International Journal of application
and innovation in Engineering & Management (IJAIEM). Vol. 3, Issue 11, November 2014
[6] Federal communication commission , First report and order ,\ Revision of part 15 of thecom-mmissions rule
regarding ultra –widebandtransmission commission FCC 2002,
[7] J. R. James, Handbook of Microstrip Antenna, Peter Peregrinus Ltd.: London, 1989.
AUTHOR
Miss.Madhuri Gaharwal completed her Bachelor of Engineering in Electronics in 2009 from Sant Gadage Baba
Amravati University.. She is currently pursuing her ME in Electronics & Communication branch from TIT college of
Excellence, RGPV University Bhopal
Volume 4, Issue 3, March 2015
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International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org
Volume 4, Issue 3, March 2015
ISSN 2319 - 4847
Prof. Ram Naresh Pal is currently working as an Assistant Professor in Electronics & Telecommunication Department
in TIT college of Excellence, RGPV University Bhopal. He is having 6.5 years of teaching experience in various
domains of E&TC branch. He is also guiding many BE and ME students for their academic projects. he published
many papers in reputed international journals and conferences.
Mrs. Poornima Pai completed her Bachelor of Engineering in Electronics in 1994 from Pune University. She is having
12 years of industrial experience and 4 years of teaching experience. She is currently completed her ME in Electronics
& Telecommunication branch from Saraswati College of Engineering. Mumbai.
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