3. Abstract
• Ultra-wideband (UWB) antennas are gaining prominence and becoming very
attractive in modern and future wireless communications systems.
• This project proposes Microstrip Fed UWB Monopole Antenna with a parasitic
patch. A fractal binary tree is introduced to achieve a passband frequency of 2.45 GHz
for Bluetooth application without compromising on the UWB antenna performance.
• UWB Monopole Antenna is implemented on FR 4 substrate and this antenna is
designed and optimized using HFSS.
• The results namely Return loss, Radiation pattern, Gain, VSWR are presented
4. Introduction
Antennas are key components of any wireless system.
An antenna is a device that transmits and/or receives electromagnetic waves.
An antenna is basically a transducer. It converts radio frequency (RF) electrical
current into an electromagnetic (EM) wave of same frequency
An antenna may be a piece of conducting material in the form a wire, rod or any
other Shape with excitation
5. Software used to design an Antenna
HFSS is a commercial finite element
method solver for electromagnetic
structures from analysis corp.
HFSS stands for High Frequency Structural
Simulator.
It is one of the several commercial tools
used antenna design .
6. Hardware used to measure an Antenna
• A network analyser in an instrument that measures the network parameters of
electrical network .Today network analysers commonly measure S parameters
because reflection and transmission of electrical networks are easy to measure at
high Frequencies .
7. Monopole Antenna
A monopole antenna is a class of radio antenna
consisting of a straight rod-shaped conductor,
often mounted perpendicularly over some type of
conductive surface, called a ground plane.
Monopole Antenna Consists of one side of
antenna feed line is attached to lower end of
monopole and other side is attached to the
ground plane.
Monopole Antenna used in Applications like
GSM, Bluetooth, Wireless Devices
8. Microstrip Patch Antenna
A Microstrip patch antenna consists of a conducting patch of any planar or non planar
geometry on one side of a dielectric substrate and other side is Ground Plane.
For good antenna performance, a thick dielectric substrate having a low dielectric
constant is desirable since this provides better efficiency, larger bandwidth and better
radiation.
Micro strip antennas
are also known as “PRINTED ANTENNAS”.
These are mostly used at microwave frequencies.
Micro strip patch antennas are easy to fabricate and comfortable on curved surface.
9. Feeding Techniques
Microstrip Feed:
The Conducting strip is connected
directly to the edge of the Microstrip patch.
The conducting strip is smaller in width than
the patch.
Coaxial Probe Feed:
The Coaxial feed is the inner
conductor of the coaxial connector extends
through the dielectric and is soldered to the
radiating patch, while the outer conductor is
connected to the ground plane.
.
10. Aperture Coupled Feed
In this aperture coupling the radiating
microstrip patch element is etched on the top of the
antenna substrate, and the microstrip feed line is
etched on the bottom of the feed substrate in order
to obtain aperture coupling.
Proximity Coupled Feed:
This type of feed technique is also called
as the electromagnetic coupling scheme. Two
dielectric substrates are used such that the feed line
is between the two substrates and the radiating
patch is on top of the upper substrate.
.
11. Coplanar Waveguide Feed:
Coplanar waveguide is a kind of planar transmission line structure, whose
ground and radiation patch are on the same layer of medium plate. A coplanar
waveguide feed consists of single central conductor strip surrounded by two ground
planes with equal size and separated by small gap.
12. UWB Technology
Ultra wide band is a communication
technology that can use very low energy
level for short range and high bandwidth
communications over a large portion of radio
spectrum.
As early as 2002 U.S FCC authorized the
unlicensed use of UWB. The frequency
range of Ultra wide band is between 3.1 to
10.6GHZ.
UWB has traditional applications like
Radar Imaging, Remote heart Monitoring.
Recent Applications like
* Target Sensor Data Collection
* Precision Locating.
* Tracking Applications.
* It Started to appear in high end
Smart phones.
13. Characteristics
UWB allow transmission of large amount of signal energy without interfering
conventional narrow band and carrier wave transmission in same frequency band.
UWB formerly known as Pulse Radio but FCC & ITU-R Currently define UWB as
antenna transmission for emitted signal bandwidth exceeds 500 MHz or 20% of
Center frequency.
UWB can effectively measure distance with an accuracy upto 10cm (3.9 Inches).
UWB can detect the location of a device over a range under 200 meters. However it
operates most in short ranges between 1-25 meters.
14. UWB Antenna
Ultra-wideband (UWB) antennas are gaining prominence and becoming very
attractive in modern and future wireless communication systems, mainly due to two
factors.
Firstly, people increasingly high demand for the wireless transmission rate and
UWB properties such as high data rate, low power consumption and low cost,
which give a huge boost to the UWB antennas.
Secondly, now the wireless portable device need antenna operated in different
frequencies for various wireless transmission functions, and operation bands and
functions are increasing more and more, which may result in challenges in antenna
design, such as antenna space limitation, multi antennas interference,etc.
UWB antenna can be used to replace multi narrow-band antennas, which may
effectively reduce the antenna number.
15. Advantages of UWB Antenna
Small in size.
Low cost.
Low power consumption.
High data rates.
Effective at achieving broad bandwidth, especially compared to conventional
narrow-band antennas.
16. Types of UWB Antenna
Along with the wireless system miniaturization and operation frequency increasing
some novel types of Omni-directional UWB Antennas have developed in the last
decade.
There are mainly consisting of two types of UWB antennas are there. They are
1. UWB Monopole Antenna.
2. UWB Printed Antenna.
From the above Types of UWB Antenna we proposed UWB Monopole Antenna
17. Design Of UWB Monopole Antenna
The size of the proposed antenna is taken as 33.3 mm ×
24.4 mm . The antenna is fabricated on an FR4 substrate
with relative permittivity of 4.4 having a standard
thickness of 1.6mm.
Here, 9.5 mm is chosen for a large circle radius as it
gives 4 GHz as lower resonance frequency with good
matching in a higher frequency band.
A fractal binary tree is introduced to achieve a pass band
frequency of 2.45 GHz for Bluetooth application without
compromising on the UWB antenna performance.
The antenna resonates at an operating frequency of 9.21
GHz which is a good candidate for integrated Bluetooth
and UWB systems.
23. Application Potential
WLAN and WiMAX are the two essential technologies flourishing in the modern
communication world. There is a huge demand for Ultra-Wideband Monopole
antennas in wireless communication.
Today Ultra Wide Band Chips are cheap and small enough to put them inside other
devices like smart phones. Nowadays it is so precise that I phone Owner can now
point his or her phone at friends phone to transfer a file or photo.
It can protect vehicles from unauthorized access via Two Factor Authentication
UWB Antennas have wide applications in short range and high-speed wireless
systems, such as ground penetrating radars, medical imaging system, high data rate
wireless local area networks (WLAN), communication systems for military and short
pulse radars for automotive or robotics.
24. Conclusion
Ultra-wideband technology is emerged as a promising technology for
providing convenience and mobility of wireless communications to high-speed
interconnections in devices throughout the digital home and office.UWB antennas having
compact and small sizes are highly desirable and essential for easy integration into space
limited systems.
The antenna resonates at two operational frequencies i.e., 2.5 GHz and 3.3 GHz,
thus covering Bluetooth/Wi-Fi band and most of the bands of 3G, 4G, and a future
expected 5G band. At these frequencies, the VSWR is obtained to be less than 2 and
return loss to be less than -10 dB which are suitable enough for the antenna to be
operational in real-time applications.
25. Future Scope
Small sized UWB antenna structures are always desirable for several applications
especially for mobile and portable devices. Some methods like metamaterial loading, self-
complementary structures, etc. can be investigated for further reduction of the antenna
dimensions. Due to overlapping of UWB systems with reserved frequency bands of other
commercial wireless systems, the filtering of those bands is required to avoid the potential
interference. So, band notch properties can be introduced in the antenna structures designed in
this thesis as a future work
27. [6]. M. Satyanarayana, Sunil Prakash, Sudhir Kumar Sharma, A. Sudhakar “Single Band-
Notched UWB Square Monopole Antenna with Double U- Slot and Key Shaped Slot”
2015 Fifth International Conference on Communication Systems and Network
Technologies.
[7]. Dr.Amlan Dutta, Satyabrata Maiti, Amrit Mukherjee”Design of a Novel Shaped Ultra
Wideband Co-axial Feed Microstrip Patch Antenna” 2014 Fourth International
Conference on Advanced Computing & Communication Technologies.
[8]. Lei Li , Jingchang Nan, Jing Liu and Chengjian Tao “A compact UWB antenna with
triple band notch reconfigurability” International Journal of Microwave and Wireless
Technologies.
[9]. Asma Ejaz, Muhammad Zahid, Yasar Amin “Dual Band Notch Planar Patch Antenna
for UWB Applications” 2020 3rd International Conference on Computing,
Mathematics and Engineering Technologies (iCoMET).
[10]. Sharadindu Gopal Kirtania , Bachir Adham Younes , Abdul Rakib Hossain, Tutku
Karacolak and Praveen Kumar Sekhar”CPW-Fed Flexible Ultra-Wideband Antenna
for IoT Applications