Microstrip patch antenna designer

1. Design of Micro-strip slot
Antenna with polarization
PRESENTED BY :-
V. Prabhu kiran (13003306)
K. Sri Charan reddy(13003350)
Under the kind guidance of ,
Dr T. V. RAMAKRISHNA

2. Introduction
O Need of Antenna
O Progress
of Communication
system

3. AIM & OBJECTIVES
O To study Micro-strip Patch Antenna.
O To design and implement this antenna
using the software HFSS, v 13.0 .

4. How does an antenna work ?
•Antenna is one type of
transducer that converts the
electrical energy into the
electro-magnetic energy in
form of electromagnetic
waves.
•Antennas are required by
any radio receiver or
transmitter to couple its
electrical connection to the
electromagnetic field.

5. Antenna characteristics :-
•Power gain
•Directivity
•Antenna
radiation patterns
•Polarization

6. Overview of micro-strip
Antenna
O Developed after revolution in Electronic
Circuit Miniaturization & LSI in 1970.
O Used on rockets & missiles previously.
O Designer’s choice.

7. Micro-strip Patch Antenna
What is Micro-strip Antenna ?
A Micro-strip patch antenna
consists of a radiating patch
on one side of a dielectric
substrate which has a ground
plane on the other side.
Invented by Bob Munson
in 1972 (but earlier work
by Dechamps goes back
to1953).

8. Different Parameters of Micro-
strip Antenna
OL = Length of the Micro-
strip Patch Element
OW = Width of the Micro-
strip Patch Element
Ot= Thickness of Patch
Oh = Height of the Dielectric
Substrate.

9. Basic Principles of Operation
•The patch acts approximately
as a resonant cavity (short
circuit walls on top and
bottom, open-circuit walls on
the sides).
•In a cavity, only certain
modes are allowed to exist, at
different resonant frequencies.
• If the antenna is excited at a
resonant frequency, a strong
field is set up inside the
cavity, and a strong current on
the (bottom) surface of the
patch. This produces
significant radiation (a good
antenna).

10. Different Shapes of Micro-strip Patch
Elements

11. Advantages of Micro-strip Patch
Antenna
•Light weight and low volume.
• Low profile planar configuration which can be easily made
conformal to host surface.
• Low fabrication cost, hence can be manufactured in large
quantities.
• Supports both, linear as well as circular polarization.
• Can be easily integrated with microwave integrated circuits
(MICs).
•Capable of dual and triple frequency operations.
• Mechanically robust when mounted on rigid surfaces.

12. Disadvantages:-
•Narrow bandwidth
•Low efficiency
•Low Gain
•Extraneous radiation from feeds and junctions
•Poor end fire radiator except tapered slot antennas
• Low power handling capacity.
• Surface wave excitation.

13. Feed Techniques:-
Micro-strip antenna can be feed by variety of methods.
This methods can be classified into two categories-
contacting and non-contacting. The foremost popular
feed techniques used are :-
O Micro-strip line.
O Co-axial probe
O Aperture coupling
O Proximity coupling

14. Software used to design Micro-strip
Patch Antenna
OHFSS is commercial finite
element
Omethod solver for electromagnetic
OStructures.from Anasys Corp.
OHFSS stands for High Frequency
OStructural Simulator. It is one of
the
OSeveral commercial tools used for
Oantenna design . It was developed
Oby Prof. Zontal Cendes and his
Ostudents at Carnegie Mellon
Univ.
Oin the year 1989.

15. The Design Specifications:-
• Dielectric constant(εr)=
2.2 ≤ εr≤ 12.
•Frequency (fr) = 1.85 to
1.90 GHz
•Height (h) = 0.003
λo≤h≤0.05 λo
• Velocity of light (c) =
3×10^8 ms-1 .
•Practical width (W) = W<
λo , , where λo is the free-
space wavelength
•Practical Length (L) =
0.3333λo< L < 0.5 λo

16. Calculation of Parameters:-
c= 3.8 x 10^8 m/sec
εr =11.9
fo= 1.85 GHz
Therefore,
W=31.9 mm

17. εr =11.9
h = 1.59 mm
W= 31.9 mm
Therefore ,
is euqal to 10.7611

18. εr =11.9
h=1.59 mm
W = 31.9 mm
Therefore ,
The value of is 6.72x10-1 mm

19. fo
= 1.85 GHz
= 10.7611
c= 3x108 m/sec
therefore , the value of is 24.7 mm & value of L will be 23.36
mm.

20. PATCH ANTENNA
COVERED BY AIRBOX

21. WAVE PORT

22. DETERMINATION OF CENTER
FREQUENCY USING S-PARAMETER:-

23. VSWR PLOT OF
MICROSTRIP ANTENNA

24. PERFECT E ASSIGNED TO
SUBSTRATE

25. PERFECT E ASSIGNED TO
PATCH

26. APPLICATIONS
• The use of micro-strip
antennas for integrated
phased array systems.
• Used in GPS (Sat.
Navigational System)
technology.
• Mobile satellite
communications, the
Direct Broadcast Satellite
(DBS) system & remote
sensing.
• Non-satellite based
applications- such as
medical hyperthermia.

27. CONCLUSION
OThe design of patch
antenna using ANSOFT
HFSS Software has been
shown here. Our project
on Design of Microstrip
Antenna which is based
on Microstrip Feed Line
Technique.
OMany more design
options and impletation
techniques are available.

28. REFERENCES:-
• http://en.wikipedia.org/wiki/Microstrip_antenna
• http://www.microwaves101.com/encyclopedia/anten
na_ustrip.cfm
• C. A. Balanis, “ Antenna Theory, Analysis and
Design”, JOHN WILEY & SONS,INC, New York
1997.