This paper on fractal techniques for designing microstrip antenna exhibits details of fractal geometries developed to get multiband behavior of patch resonator antenna. In this paper the review on various techniques of compactness by fractal geometry on microstrip patch antenna for X band used for satellite communication and radar application are presented.

1. www.ijeee-apm.com International Journal of Electrical & Electronics Engineering 13
IJEEE, Vol. 1, Issue 3 (June, 2014) e-ISSN: 1694-2310 | p-ISSN: 1694-2426
REVIEW OF FRACTAL TECHNIQUES FOR
DESIGNING MICROSTRIP PATCH
ANTENNA FOR X BAND1
Amanpreet Kaur, 2
Dr. Hardeep Singh Saini
1
Dept.of ECE, Indo Global College of Engineering, Mohali, Punjab, India
2
Associate Dean Academic, Indo Global College of Engineering, Mohali, Punjab, India
1
amanpreet_90@ymail.com 2
hardeep_saini17@yahoo.co.in
ABSTRACT: With advancement in communication
technology over the past decade, there is an increasing
demand for miniaturization, cost effective, multiband and
wideband antennas. Fractal antenna designs can support in
meeting these requirements. Various techniques and
geometries have been introduced for size reduction of
microstrip patch antennas. This paper on fractal techniques
for designing microstrip antenna exhibits details of fractal
geometries developed to get multiband behavior of patch
resonator antenna. In this paper the review on various
techniques of compactness by fractal geometry on
microstrip patch antenna for X band used for satellite
communication and radar application are presented.
Key words: Fractals, Antenna design techniques, Fractal
Microstrip Patch Antenna, X band.
I. INTRODUCTION
In modern wireless communication system and increasing
other wireless applications, wider band-width, is required,
traditionally each antenna operates at a single frequency
band, where a different antenna is needed for different
application. Therefore large space is required for different
antennas. In order to overcome this problem, multiband
antenna can be used where a single antenna can operate at
many frequency bands. So multiband behavior can be
achieved by fractal zing the antenna.
Fractal concepts have been increasingly applied to the
design of various antennas in recent years because of their
Self-similar characteristic and space-filling capability.
Fractals were first defined by Benoit Mandelbort in
1975[1], [2]. There are various fractal geometries which
have been investigated. These geometries have been used
to characterize unique occurrences in pattern of nature that
were difficult to define with Euclidean geometries like
length of coastlines, the clouds density, and the tree’s
branches. Many techniques have been reported to reduce
the size of various antennas and to improve the frequency
bandwidth [3]. And fractal geometries also provide the
ability of multi-band properties [4]. It describes the class
of complex geometries that are created through successive
iteration of applying a geometric generator to a simple self
similar basis. In this study, fractal geometries such as
Sierpinski gasket, Hilbert curves, Koch curves and few
generalizations of some of these are explored.
II. FRACTAL GEOMETERY
There are many fractal geometry that have been found to
developing new design for antennas [1]. Fig. 1 shows
some of these unique geometries. Most of these
geometries are infinitely sub-divisible, with each division
a copy of the parent. This special nature of these
geometries has led to several interesting features
uncommon With Euclidean geometry.
Fig. 1: Various Types of Fractals Used As Antenna
III. REVIEW
A large number of Fractal Antenna design approaches
have been proposed for wireless applications. The
overgrowing body of the literature suggests the design of
patch antenna using fractal techniques for X band. The
purpose of the survey is donated to a remarkable growth of
antenna design techniques in wireless communications
A. OCTAGON SHAPED MICROSTRIP FRACTAL
ANTENNA
The presented antenna is design with new fractal
geometry which is circle in octagon shaped [6]. This
microstrip patch antenna has been designed for the X band
applications. The antenna is capable of covering the
8GHz- 12GHz frequency band. It is observed that the third
iteration of the fractal antenna exhibits good wideband
characteristics, which can be used in wireless application
such as, terrestrial broadband, armature radio and satellite
communication. The dimensions of the ground plane are
60x60 mm. The antenna is placed on fr4 substrate with Ԑr
= 4.4 and thickness 0.25mm. CPW feed of length 11.2mm
and width 2mm is given to the patch [5]. Antenna is
designed using High Frequency Structured Simulator
(HFSS) software. The patch is a perfect – E conductor.
The third iteration is found to have improved antenna

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parameters compared to the first and second. It is observed
that the return loss characteristics reduce as the number of
iteration increase. In 8GHz – 12GHz, a wide bandwidth of
3.2112GHz is obtained in the range of 8.53GHz –
11.7470GHz for the third iteration. It is observed that
wideband characteristics have improved, as number of
iteration increase, due to the current along its edges. The
geometry of antenna is described in fig. 2.
Fig. 2: Octagon Shaped Fractal Microstrip Antenna
B. FAN SHAPE FRACTAL ANTENNA
A novel fan shaped fractal antenna based on sierpinski
gasket fractal geometry. The design and simulation of Fan
shape fractal antenna has done using IE3D
electromagnetic simulation software[7]. This fan shape
fractal antenna gives better performance in return loss,
efficiency and directivity. This fractal antenna can be used
for X band applications and also used in Wi-Fi. This
antenna was designed using FR4 EPOXY substrate with
height is h = 2.5 and Ԑr = 4.4. This behavior is obtained
using coaxial probe fed method. In all iteration feeding
point is same and radius of feeding point is 0.25mm. In
this work, a fan base is taken and another shape of
sierpinski gasket is cut from it. Same procedure is repeated
and the result of simulation studies is presented up to
second iteration. In the base shape a fan shape of radius
13mm is taken. For the first iteration one sierpinski gasket
geometry has length and width of 4mm and 6mm
respectively is cut from the geometry. In the second
iteration two sierpinski gasket geometry is cut from the
geometry as shown in figure 5. The shape of the second
iteration is 1/2 of the first iteration. It is observed that as
the fractal iteration increases, the antenna is now resonant
at more frequencies. In this design two bands are occurs
at 8.5 GHz and 9.5 GHz. In the second iteration, we got
the minimum resonant frequency with return loss -21.19
dB at 8.5 GHz, whose bandwidth is 8.82 %. This antenna
providing a gain of 5.77dB at 8.5 Ghz. The bandwidth
effect changes with the change in resonant frequencies and
VSWR is within the accepted level.
The geometry of antenna is described in fig. 3.
Fig. 3: Fan shape fractal antenna
A. COPLANER RECTANGULAR PATCH
ANTENNA
An inset fed Coplanar Patch Antenna [8] designed for X
band satellite communication. This antenna provides high
radiation efficiency and wider bandwidth therefore it could
be applicable in many X band satellite systems. It provides
98% radiation efficiency. A coplanar patch antenna has
ground and patch on the same side of the substrate.
Antenna is designed using High Frequency Structured
Simulator (HFSS v13) software. The coplanar patch
antenna structure design has following specification [8]
length and width is calculated as L=4.3mm, W=10.5mm.
The coplanar patch antenna is placed on Rogers/RT duroid
5880 substrate. Substrate height h=0.508mm, permittivity
of the substrate εr = 2.2, dielectric loss tangent = 0.0009
and operating frequency is 10 GHz. The strip gap (s) is
taken as 0.2mm and width (W) of the coplanar waveguide
feed is 1.252mm. Coplanar patch antenna model has a
resonance frequency at 10.0557GHz and has a return loss
of -32.2009dB. Coplanar patch antenna has an impedance
bandwidth of 17.75% (i.e. 1.785GHz) and coplanar patch
antenna has 2.79dB directivity value. Due to its high
radiation efficiency and wide bandwidth it can be
applicable in satellite transponders and in military
RADAR and satellite communication systems.
The geometry of antenna is described in fig. 4.

3. www.ijeee-apm.com International Journal of Electrical & Electronics Engineering 15
Fig.4: Model of Coplanar Patch Antenna in HFSS software
IV. CONCLUSION
This review work provided an insight in determining the
performance of microstrip patch antenna using various
fractal techniques. From this we conclude that there are
many Fractal techniques that used to design a microstrip
patch antenna for X band application such as satellite
communication, armature radio and radar application. This
paper also exposed a Literature Review Table of different
techniques.
REFRENCES
[1] Benoit B. Mandelbrot, The Fractal Nature of Geometry, New
York, W. H. Freeman and company, 1977.
[2] Ved Vyas Dwivedi, Ph. D. Thesis, ‘ Design and Development
of Dual/Tri band miniaturized and compact antenna using
metamaterial’,2010.
[3] P.E. Mayes, Frequency-independent antenna and broad-band
derivatives thereof, Proc IEEE 80, 1992, 1103–1123.
[4] Lars Josefsson and Patrik Persson. "Conformal Array
Antenna Theory and Design," The IEEE Press Series on
Electromagnetic Wave Theory. 2006.
[5] An Overview of Fractal Antenna Engineering Research by
Douglas H. Werner and Suman Gangul, IEEE Antennas and
Propagation Magazine, Vol. 45, NO. I, February 2003.
[6] B. Hephzibah Lincy A. Srinivasan B.Rajalakshmi, “X – Band
Fractal Microstrip Antenna for Wireless Application”,
International Journal of Computer Applications (0975 – 8887)
Volume 68– No.3, April 2013
[7] Yogesh Bhomia , Devesh Kumar Singh Rathore, “Design and
Simulation of Fan Shape Fractal Antenna for X-Band
Application”, International Journal of Electronics and Computer
Science Engineering.
[8] Arvind Singh Jadon, Jalaj Sharma, Ajay Prajapat, Avanish
Bhadauria, “Coplanar Rectangular Patch Antenna for X Band
Applications Using Inset Fed Technique”, International
Conference on Communication Systems (ICCS-2013) Special
Issue (November 2013), pp.95-10.
Table 1: Literature Review Table
S.No
.
Antenna Design Frequency
Band
Return loss Gain APPLICATION FOR X band
1. Octagon Shaped Fractal
Microstrip Antenna
8.53GHz
11.7470GHz
-24 dB 7dB Terrestrial broadband, armature radio
and satellite communication.
2. Fan Shape Fractal
Antenna
8.5 GHz and
9.5 GHz
-26.79 dB at 9.5
GHz
-21.19 dB at 8.5
GHz
5.77dB Wi-Fi
3. Coplanar Rectangular
Patch Antenna
10.0557GHz -32.2009dB 2.79dB satellite transponders and in military
RADAR and satellite communication
systems