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ISSN: 2395-0560 International Research Journal of Innovative
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Study and Performance Analysis of UWB Antenna for UWB
Ccommunication Systems Hridesh Kumar Verma1, Dr. Praveen Kumar
Maduri2, Deepanshu Bhargava3, Gaurav Yadav4,
Himanshu Pandey5
1, 2,3,4,5 Department of Electronics and Instrumentation
Galgotias College of Engineering and Technology, Greater
Noida-201306
Abstract In this article, recent papers on UWB antennas are
studied; different geometries, design parameters and their
experimental results are discussed. Several types of UWB antennas
in recent papers are described together while comparing their
measured dimension, gain and radiation patterns. The circuits have
taken into consideration uses various substrate materials with
different dielectric constants. The performance of the various
circuits has been observed by comparing various parameters.
INTRODUCTION
In this paper we have compared and analyzed four different UWB
antenna circuits presented in different journals. The first circuit
we took into consideration was presented by Rezaul Azim and
Mohammad Tariqul Islam. They discussed about a compact micro strip
line-fed ultra wideband (UWB) tapered-shape slot antenna in their
paper named Compact Tapered-Shape Slot Antenna for UWB Applications
in 2011[1]. Further in the second circuit considered, Jian Yang and
Ahmed Kishk novel compact low-profile directional UWB antenna. The
paper was published in march 2012, named as A novel compact
low-profile directional UWB antennathe self-grounded Bow-Tie
antenna[2].The third circuit that we studied was presented by Anil
Kr Gautam, Swati Yadav and Binod Kr Kanaujia in 2013 .This paper
was published under the name A CPW-Fed Compact UWB Micro strip
Antenna[3]. In this paper, the authors have proposed a novel
coplanar waveguide (CPW)-fed compact ultra wideband (UWB) micro
strip antenna for ultra wideband applications. Finally the fourth
paper we discussed was published by Thomas Peter, Tharek Abd
Rahman, S. W. Cheung, Rajagopal Nilavalan, Hattan F. Abutarboush
and Antonio Vilches named A Novel Transparent UWB Antenna for
Photovoltaic Solar Panel Integration and RF Energy Harvesting [4].
The paper was published in the year 2014. In this paper a
transparent cone top tapered slot antenna covering the frequency
range from 2.2 to 12.1 GHz has been designed.
The admiral benefits of a wireless lifestyle have resulted in a
huge demand for advanced wireless communications. The quick
tempered growth of the wireless coomunication market is expected to
continue in the future since the claim of all wireless services is
increasing.
Transparent antennas for communications have been researched on
by only a dedicated few for the last two decades .An antenna is a
transducer that transforms guided electromagnetic energy in a
transmission line to radiated electromagnetic energy in free space.
Antennas may also be viewed as an impedance transformer, coupling
between an input or line impedance, and the impedance of free
space. [5] In 2002, the Federal Communications Commission (FCC)
allocated the spectrum from 3.1 to 10.6 GHz [Fig.1] for unlicensed
ultra wideband (UWB) measurements and communication applications
with EIRP less than 41.3 dB/MHz. Since then, UWB has been
considered as one of the most promising wireless technologies to
revolutionize high data transmission.
. Figure. 1 Bandwidth allocation
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ISSN: 2395-0560 International Research Journal of Innovative
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At present, attractive characteristics of ultra wideband (UWB)
technology like low cost, low complexity, low spectral power
density, high data resolution, very low interference, and extremely
high data transmission rates have made it a potential candidate in
various wireless communications. For different wireless
communication applications, a UWB antenna must be electronically
small and inexpensive without degrading the performance. Stable
omnidirectional radiation patterns, gain flatness, and linear phase
variation are also required to fulfill the requirements for UWB
applications. [1] Thus, the UWB antenna has become the most
promising solution for future short-range, high-data, wireless
communication applications, UWB for short-range (10 m),
peer-to-peer ultra-fast communications, and many more application.
The imminent widespread commercial deployment of ultra-wideband
(UWB) systems has sparked renewed interest in the subject of
ultra-wideband antennas. UWB antennas have been in active
commercial use for decades. In a sense, even the venerable AM
broadcast band antenna is UWB since it covers a band from 535- 1705
kHz for a fractional bandwidth in excess of 100%. Because a high
quality broadcast AM antenna is really a tuned antenna designed to
pick up an individual narrowband (10 kHz) channel, the effective
fractional bandwidth is really only 0.6-1.9% and only one channel
can be received at a time. UWB antenna is usually preferred as UWB
technology transmit and receive pulse based waveform compressed in
time. Because of compressed time pulse data rate is very high and
as the power of pulse is spread over the large frequency band so
noise interference is very less.
Many planar antennas have been anticipated for UWB applications.
Among planar UWB antennas, the printed slot antenna type is one of
the most suitable candidates for UWB applications. A conventional
narrow slot antenna has limited bandwidth, whereas wide-slot
antennas exhibit wider band-width. Recently, different printed
wide-slot antennas fed by a micro strip line or coplanar waveguide
(CPW) have been reported. The monopole-like slot antennas have also
been reported to have wide bandwidth characteristics in. By using
different tuning techniques or employing different slot shapes,
different slot antennas with wide- band or ultra-wide band
performance can also be achieved. In addition, a UWB antenna is
preferentially non- dispersive, having a fixed phase center. If
waveform dispersion occurs in a predictable fashion it may be
possible to compensate for it, but in general it is desirable to
radiate similar waveforms in all directions. A log- periodic
antenna is an example of a dispersive antenna. Larger scale
components radiate low frequency components while smaller scale
components radiate high frequency components. The result is a
chirp-like, dispersive waveform. Worse, the waveform will vary at
different azimuthal angles around the antenna. Again, a multi-band
or OFDM approach may be more tolerant of dispersive antennas.
[6]
HISTORY of UWB ANTENNA
Ultra-wideband has its origins in the original spark-gap
transmitters that initiated radio technology. [7] UWB systems have
been historically based on impulse radio since it has transmitted
very high data rates by sending pulses of energy instead of using a
narrowband frequency carrier. The concept of impulse radio dates
back to the pulse based spark gap radio developed by Guglielmo
Macroni in the late 1800s. It was used for several decades to
transmit Morse code through the airwaves. Ironically, the very
patent which initiated the concept of narrowband frequency domain
radio also revealed some of the first ultra-wideband antennas. In
1898, Oliver Lodge presented the idea that a transmitter and a
receiver should be tuned to the same frequency so as to maximize
the received signal. Lodge disclosed spherical dipoles, square
plate dipoles, biconical dipoles, and triangular or bow-tie
dipoles. He also introduced the concept of a monopole antenna using
the earth as a ground.
Figure 2: Lodge preferred antennas
As frequencies increased and waves became shorter, the economic
advantages of a thin-wire quarter wave antenna superseded any
performance advantages of Lodges original designs. With the advent
of research into television however, interest in antennas that
could handle the much wider bandwidths associated with video
signals increased.
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ISSN: 2395-0560 International Research Journal of Innovative
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Figure 3: Lodges biconical antennas (1898).
This renewed interest in wideband antennas led to the discovery
of different type of antenna by researchers which improves the
Lodges original designs and also led to high performances. Figure
4a and 4b shows the improved version of Lodges Antennas.
Figure 4a (left): Carters biconical antenna (1939)
Figure 4b (right): Carters conical monopole (1939).
The most notable UWB antenna of that period was Lindenblads
coaxial horn element shown in Figure 5. Lindenblad improved on the
idea of a sleeve dipole element, adding a gradual impedance
transformation to make it broader banded. For several years during
the 1930s, a turnstile array of Lindenblads coaxial horn elements
graced the top of the Empire State Building in New York City where
RCA located its experimental television transmitter.
Figure 5a (left): Lindenblads element in cross- section Figure
5b (right): A turnstile array o f L i n d e n b a l d elements for
television transmission (1941).
In the late 1960s, significant research was conducted by antenna
designers. As a result of these antenna advances, the development
of short pulse radar and communication systems has begun. For the
nearly 40 year period of 1960-1999, over 200 papers were published
in accredited IEEE journals and more than 100 papers were filed on
topics related to ultra wide band technology.[8]
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ISSN: 2395-0560 International Research Journal of Innovative
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Although standing designs presented excellent performance, other
consideration began to become important. As broadband receivers
came into common use, emphasis on inexpensive, easily manufactural
designs increased.On February 14, 2002, FCC permitted the
commercial operation of UWB technology. After this official
permission, research interest has exponentially grown with several
researchers exploring RF, circuit, system and antenna designs
related to UWB technology.
DESIGN AND ANALYSIS OF VARIOUS CIRCUITS:
I. Compact Tapered-Shape Slot Antenna for UWB Applications
Rezaul Azim and Mohammad Tariqul Islam discussed about a compact
micro strip line-fed ultra wideband (UWB) tapered-shape slot
antenna. The proposed antenna comprises a tapered-shape slot and
rectangular tuning stub. The antenna is fabricated onto an
inexpensive FR4 substrate with an overall dimension of 22 X 24
mm.
Figure 6: Schematic diagram of the proposed antenna. (a) Top
view. (b) Back view.
Influence of the parameters on antenna performance:
Effect of Tuning Stub-In order to optimize the coupling between
the micro strip line and the tapered slot, the rectangular stub was
taken which shows a good coupling with the tapered-shape slot,
providing a wider impedance matching for UWB applications. Effect
of Slot Shape- Introduction of the tapered slot instead of the
rectangular slot changes the electric eld distribution by reducing
the longest current path and reducing the slot size. It is also
observed that high-frequency performance can also be improved by
employing tapered slot structure. Effect of Feeding Gap- The gap
between the slot and the ground plane determines the matching
between the feed line and slot antenna. It is observed that a feed
gap of 0.75 mm can give the widest operating band.
ANALYSIS AND RESULT:
The impedance characteristics of the proposed antenna were
calculated using the full-wave electromagnetic simulator IE3D.
Figure 2 represents measured phase of input impedance.
Figure 7: Measured phase of the input impedance.
Radiation pattern- It can be observed that at the low frequency
of 3.4 GHz, the radiation pattern in the XY-plane is
omnidirectional with low cross-polarization values.
Figure 8: radiation pattern at 3.4GHz frequency.
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ISSN: 2395-0560 International Research Journal of Innovative
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The stable radiation pattern with a maximum gain of 5.4 dBi
makes the proposed antenna suitable for being used in UWB
communication applications.
II. Self-Grounded Bow-Tie Antenna
Jian Yang and Ahmed Kishk discussed novel compact low-profile
directional UWB antennathe self-grounded Bow-Tie antenna. The
antenna has a simple geometry, ultra-wideband performance with
about 10-dB reflection coefficient and stable radiation beams for
the frequency range of 215 GHz, and good time-domain impulse
response.
Figure 9: Different dimensions used
Figure 9 is showing all the different dimensions used. In this
paper the width of the antenna is fixed as 140 mm, and the extended
angle has been chosen as 60, 90, and 120, and therefore, the length
of the antenna is changed correspondingly. The substrate used is
Rogers RO403 board. The radiation pattern is stable having a
reflection coefficient of -10db. ANALYSIS AND RESULT:
Figure 10: Simulated reflection coefficients of the three
self-grounded Bow-Tie antennas of different extended angles.
The infinite Bow-Tie dipole is a planar scaled structure and
therefore is a frequency-independent antenna. In order to have a
directional radiation (radiating mainly in one direction), a
seagull-over-sea configuration of infinite Bow-Tie antenna is a
natural choice, see Figure 10, which is also a scaled structure
with the frequency-independent characteristics.
Figure 11: Seagull-over-sea configuration of Bow-Tie.
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ISSN: 2395-0560 International Research Journal of Innovative
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The new UWB antenna has many unique characteristics: compact
size, low profile and at the same time directive radiation
function, low reflection coefficient, and good time domain impulse
response. It can be foreseen that the self-grounded Bow-Tie antenna
will find many applications in UWB communication systems, UWB radar
and tracking systems, UWB indoor geolocation systems, UWB sensing
and microwave tomography, and more. Further development on this UWB
antenna and its applications will be reported in the near
future.
III. A CPW-Fed Compact UWB Microstrip Antenna
Anil Kr Gautam, Swati Yadav and Binod Kr Kanaujia proposed a
novel coplanar waveguide (CPW)-fed compact ultra wideband (UWB)
micro strip antenna for ultra wideband applications. The proposed
antenna holds a method to curtail the monopole antenna by loading
of inverted L-strip over the conventional monopole patch antenna to
lower the height of the antenna. The ground was vertically extended
toward two sides of the single radiator. The prototype with overall
size of 25 X 25 X 1.6 mm achieves good impedance matching, constant
gain, stable radiation patterns, and constant group delay over an
operating bandwidth of 2.6-13.04 GHz (10.44GHz). This UWB antenna
was fabricated and printed on a 1.6-mm-thick FR-4 substrate with
permittivity of 4.4 and a loss tangent of 0.024.
Figure 12: Schematic configuration of the proposed compact UWB
microstrip antenna.
The inclusion of the two inverted L-shaped strips in the
proposed design will significantly improve the impedance-matching
conditions for the entire UWB and shows three resonant bands at
3.03, 6.11, and 11.78 GHz. ANALYSIS AND RESULT: The simulated group
delay of the proposed antenna is shown in Figure 13. As it can be
seen, the variation of the group delay for the proposed antenna is
almost constant (remains nearly 1 ns) for the entire UWB band. This
confirms that the proposed UWB antenna is suitable for UWB
communication.
Figure 13: Group delay for the proposed UWB
Figure 14 shows the measured and simulated 2-D far-field
radiation patterns in the H-planes and E-planes at sampling
frequencies of 3.03, 6.11, and 11.78 GHz resonance frequencies,
respectively. It is found that the antenna has nearly good
omnidirectional radiation patterns at all frequencies in the
E-plane and the H-plane. This pattern is suitable for application
in most wire- less communication equipment.
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ISSN: 2395-0560 International Research Journal of Innovative
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Figure 14: Radiation pattern for various resonance frequencies
For the proposed compact UWB microstrip antenna
The good impedance-matching characteristic, constant gain and
omnidirectional radiation patterns over the entire operating
bandwidth of 2.613.04 GHz (10.44 GHz) make this antenna a good
candidate for UWB applications and systems.
IV. A Novel Transparent UWB Antenna for Photovoltaic Solar Panel
Integration and RF Energy Harvesting Thomas Peter, Tharek Abd
Rahman,S. W. Cheung,Rajagopal Nilavalan,Hattan F. Abutarboush and
Antonio Vilches designed a transparent cone top tapered slot
antenna covering the frequency range from 2.2 to 12.1 GHz and
fabricated to provide UWB communications whilst integrated onto
solar panels as well as harvest electromagnetic waves from free
space and convert them into electrical energy. The antenna when
sandwiched between a-Si solar panel and glass is able to
demonstrate a quasi-Omni-directional pattern that is characteristic
of a UWB.
Figure 15: (a) Geometry of CTSA and (b) prototype of CTSA
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ISSN: 2395-0560 International Research Journal of Innovative
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Table 1 DIMENSION (MM) OF THE ANTENNA GEOMETRY IN FIG.
The antenna is first studied laminated on a 2-mm-thick glass,
and later sand- wiched between the 2-mm-thick glass and an a-Si
solar panel. Measurement of solar energy- The measurements are done
in the ambient light of fluorescence lighting as well as outdoor in
the sun. The solar panel has a conversion rate of more than 15% and
is able to deliver a voltage of 5.5 V and a current of 70 mA as per
the manufacturers specification in free space.
Measurement of RF energy- A single-tone RF signal is generated
using a signal generator and fed to a horn antenna. The rectenna
placed at a certain distance is used to collect the RF signal
transmitted from the horn and convert it to dc power. The amount of
dc converted is used to measure the performance of the
rectenna.
ANALYSIS AND RESULT:
The simulated and measured return losses of the CTSA in free
space, laminated on the a-Si solar panel and sandwiched between the
solar panel and 2-mm glass superstrate are all shown in Figure 16
for comparison.
Figure 16. Simulated and measured return loss of CTSA in free
space, on solar panel only, and sandwiched between solar panel and
glass The measured radiation patterns in the X-Y direction at two
frequencies are depicted in figure 17 .The measured radiation
patterns for the sandwich configuration are seen to be quasi-omni
directional for different frequencies tested at 3 and 5 GHz.
Figure 17: Radiation pattern at 3 GHz and 5 GHz
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In this paper, a novel transparent UWB CTSA that can maintain
its Omni- directionality when integrated onto solar panels as well
as harvest RF energy, besides being able also to provide wireless
communication has been presented. CONCLUSION
In conclusion, the various circuits involving UWB antenna have
been observed and their results have been analyzed. The analysis is
done by comparison between measured and simulated result of the
circuits and by comparing various parameters such as bandwidth,
shape, dimension, substrate, radiation pattern etc. In conclusion,
the various circuits involving UWB antenna have been observed and
their results have been analyzed. The analysis is done by
comparison between measured and simulated result of the circuits
and by comparing various parameters such as bandwidth, shape,
dimension, substrate, radiation pattern etc. On observing various
parameters, Self-Grounded Bow-Tie antenna has maximum bandwidth
(2-15 GHz). The shape of this antenna is compact and simple and the
radiation pattern is also stable (-10db reflection
coefficient).This antenna is used in UWB Indoor geolocation system
Radar and Tracking system. Hence, the Self Grounded Bow- Tie
antenna is most suitable.
REFRENCES
[1] Azim, Rezaul, Mohammad Tariqul Islam, and Norbahiah Misran.
"Compact tapered-shape slot antenna for UWB
applications." Antennas and Wireless Propagation Letters, IEEE
10 (2011): 1190-1193. [2] Yang, Jian, and Ahmed Kishk. "A novel
low-profile compact directional ultra-wideband antenna: the
self-grounded Bow-Tie
antenna." Antennas and Propagation, IEEE Transactions on 60.3
(2012): 1214-1220. [3] Gautam, Anil Kr, Swati Yadav, and Binod Kr
Kanaujia. "A CPW-fed compact UWB microstrip antenna." IEEE antennas
and
wireless propagation letters 12 (2013): 151-154. [4] Peter,
Thomas, et al. "A novel transparent UWB antenna for photovoltaic
solar panel integration and RF energy
harvesting." Antennas and Propagation, IEEE Transactions on 62.4
(2014): 1844-1853. [5] Schantz, Hans Gregory. "Introduction to
ultra-wideband antennas." IEEE conference on ultra wideband systems
and
technologies. Vol. 2993. 2003. [6] Balanis, Constantine A.
Antenna theory: analysis and design. John Wiley & Sons, 2012.
[7] Schantz, Hans Gregory. "A brief history of UWB antennas." IEEE
Aerospace and Electronic Systems Magazine 19.4 (2004):
22-26. [8] Barrett, Terence W. "Technical features, history of
ultra wideband communications and radar: part I, UWB
communications." Microw J 44.1 (2001): 22-56.
PARAMETERS Compact Tapered Shape Slot Antenna
Self-Grounded Bow Tie Antenna
CPW fed Compact UWB Antenna
Novel transparent UWB Antenna (for solar panel)
BANDWIDTH 3-11.2 GHz 2-15 GHz 2.6 -13.04 GHz
2.2-12.1 GHz
SHAPE Tapered shape slot Rectangular stub
Novel low profile , Compact and simple geometry
Noval coplanar -
DIMENSION 22*24 mm2 Thickness-1.6mm
L= 58mm (=60 0) L=100mm (=900) L=166mm (=1200mm)
25*25*16mm3
Thickness=2mm Overall size 17*33.5mm2
SUBSTRATE FR4 r = 4.50 tan=0.0180
Rogers RO403 board r =3.38 Tan=0.027
FR-4 r = 4.4 Tan=0.02
AgHT-4