Design and analysis of various types of Micro Strip Antennas Under esteemed guidence
of Mr.J.Lakshmi Narayana M.Tech,Ph.D
D.L.Pavan kumar
J.Anusha
B.Manikanta
K.Vidya rani
M.Sampath kumar
Introduction to Micro Strip Antennas In genaral Micro strip antennas are also known as
“ PRINTED ANTENNAS ”.These are mostly used at microwave
frequencies Because the size of the antenna is directly
tied the wavelength at the resonant frequency.Micro strip patch antenna or patch antenna is
a narrowband wide-beam antenna.The patch usually fed along the centerline
to symmetry and thus minimize exitation of
undesirable modes.
Micro strip antennas are easy to fabricate and comfortable on curved surface .
The directivity is fairly insensitive to the substrate thickness.
Micro strip patch antennas
patches are in variety of shapes ,
such as rectangular , square ,
triangular and circulator
Aim: The design and analysis of various micro strip patch
antennas such as rectangular ,square ,circular and arrays are proposed in this project .
An artificial neural network model are to be developed for proposed micro strip antennas .
A comparative study on the performance of various micro strip antennas i.e between square , circular,rectangular antennas are observed.
Patch Shapes Are:
Other Shapes Are :
Substrates are:The most commonly used substrates are, 1) Honey comb(dielectric
constant=1.07) 2)Duroid(dielectric constant=2.32) 3)Quartz(dielectric constant=3.8) 4)Alumina(dielectric constant=10) A thicker substrate will increase the
radiation power , reduce conductor loss and improve Band width.
Feeding Techniques:Coaxial feedMicrostrip feedProximity coupled microstrip feedAperture coupled microstrip feedCoplanar wave guide
Among all the feeds most prefarable one is coaxial feed.Because impedence matching is achived through this feed .This feed is using huygen’s principle modeled by cylindrical band of electric current.
Comparision of various types of flat profile printed antennas:Charaterstics Microstrip
patch antennaMicrostrip slot antenna
Printed diploe antenna
Profile Thin Thin Thin
Fabrication Very easy Easy Easy
Polarization Both linear& circular
Both linear& circular
Linear
Dual freq operation
Possible Possible Possible
Shape Any shape Rec &circle Rec &tiangular
Spurious radiation
Exists Exists exists
Softwares used:For design and simulation we are using ‘MAT
LAB’ softwareFor analysis we are using the ‘SONET’ and
‘AN-SOFTWARE.For artificial neural networks model we are
using the different simulation softwares.
Advantages:Easy to fabricate on curved surfacesEasily integratedDual frequency and dual polarization can be
easily made.Linear and circular polarization is possibleLow cost , Less sizeCan be integrated in microwave circuits
Disadvantages:Narrow bandwidth associated with
Tollerence problemLower gain(nearly 6db)Large ohmic losses in feed structure of arraysExitation of surface wavesMost microstrip antetnnas radiate into half-
space
Remedies:Low power and low gain can overcome by
arrays configuration.Surface wave associated limitations such as
poor efficiency,increased mutual coupling,reduced gain and radiation pattern can overcome.
The band width can increase upto 60% by using some special techniques.
Applications:Used in mobile satellite communication
system.Direct broad cast telivision(DBS).Wire less LAN’S.Feed elements in coaxial system GPS system.Missiles and telementry
Microstrip antenna used in robot:
References:Microstrip antenna design hand book Author: BAHL and BHARTIAAnalysis and design of microstrip antennas Author :Alka Verma Microwave journal Author:Pasquale Dottorato