RUSTAMJI INSTITUTE OF TECHNOLOGY BORDER SECURITY FORCE TEKANPUR GWALIOR (M.P)

PRESENTATIONON

DESIGN OF RECTANGULAR PATCH ANTEENA USING METAMATERIAL SUBSTRATE

SUBMITED TO SUBMITED BY NEERAJ SHRIVASTAVA PRATEEK KUMAR (HOD OF ELECTRONICS AND COMMUNICATION DEPARTMENT) 0902EC13MT 09

COMMUNICATION SYSTEMMTECH 2ND YEAR

ANTEENA ?

ANTENNA IS A TRANSDUCER DESIGNED TOTRANSMIT OR RECEIVE ELECTROMAGNETICWAVES .

OBJECTIVES OF THE PROJECT

• The main objectives of this project are:

i) To prove the concept of metamaterial.

ii) To reduce the size of rectangular patch antenna by implementing metamaterial as substrate.

iii) To compare the performance of DGS and conventional antenna.

MY WORK

• the development of two rectangular patch antenna using DGSs that functions at 4.7 GHz and 2.4GHz

• Then, produce the metamaterial substrate by using DGS.

• substrates are then tested through simulation using NRW method to find the metamaterial functional frequency.

• both conventional and DGS antennas are designed USING CST SOFTWARE

•All simulation for conventional and DGS antennas had been done in CST ENVIRONMENT

• Thus, the size and performance of conventional and DGS antenna are compared.

•Fabrication will made to verify the simulation results.

ANTENNA TYPES

i. Active integrated antennas

ii. Antenna arrays (including smart antennas)

iii. Dielectric antennas (such as dielectric resonant antennas)

iv. Microstrip antennas (such as patches)

v. Lens antennas (sphere)

vi. Wire antennas (such as dipoles and loops)

vii. Aperture antennas (such as pyramidal horns)

viii. Reflector antennas (such as parabolic dish antennas)

ix. Leaky wave antennas

MICROSTRIP ANTENNA

Antenna Patch

Dielectric substrate

Ground plane

Microstrip patch antenna consists of a radiating patch on

one side of a dielectric substrate which has a ground plane

on the other side.

SHAPES OF MICROSTRIP

PATCH .

Different Parameters of Micro-strip

Antenna

•L = Length of the Micro-strip Patch Element

•W = Width of the Micro-strip Patch Element

•t= Thickness of Patch

•h = Height of the Dielectric Substrate.

Calculation of Parameters:-

The equation to realize the conventional rectangular patch antennas are shown as below:

The effective dielectric constant of a microstrip line is given by

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 :-

• Micro-strip line.

• Co-axial probe

• Aperture coupling

• Proximity coupling

Microstrip Line Feed

• Microstrip line feed is a feeding method where a conducting strip is connected to the patch directly from the edge

The simplified calculation for the length of the inset cut shown by equation

where:l = the inset cut lengthεr = Permittivity of the dielectricL = Length of the microstrip patch

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 multi frequency operations.

• Mechanically robust when mounted on rigid surfaces.

• useful in aircraft, satellites and missile applications,

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.

APPLICATIONS

• The use of micro-stripantennas for integratedphased array systems.

• Used in GPS (Sat.Navigational System)technology.

• Mobile satellitecommunications, theDirect Broadcast Satellite(DBS) system & remotesensing.

• Non-satellite basedapplications- such asmedical hyperthermia.

Many methods are used to reduce the size of MPA like ----using planar inverted F antenna structure (PIFA)

or using substrate with high dielectric constant

Defected Ground Structure (DGS) is one of the methods to reduce the antenna size.

The substrate with DGS is considered as metamaterial substrate when both relative permittivity, εr and permeability, μr are negative.

• metamaterial antenna will have good performance and smaller size to conventional one.• . The metamaterial antenna behaves as if it were much larger than it really is.

• extending the bandwidth, DGS approaches can also be utilized.

Due to the increment of the side and back radiation. the

front lobe or main lobe will decrease which lead to

reduction in gain.

Conventional antenna follows the right-hand rule metamaterial

antenna follows the left-hand rule

•conventional antenna radiates at frequency of half wavelength of the

patch length while metamaterial antenna able to radiates having

smaller size of antenna

•project emphasize on obtaining the metamaterial using DGS

METAMATERIAL

• Metamaterial is a material having negative relative permittivity and permeability. These

• two properties determine how a material will interact with electromagnetic radiation.

• Metamaterial substrates are synthesized by combining electric and magnetic dipole elements.

Figure 2.20: Structure used for metamaterial synthesis (a) SRRs , (b) metal wire lines, (c) CSRRs,(d) slot lines

DGS

• The concept of DGS arises from the studies of Photonic Band Gap (PBG) structure which dealing with manipulating light wave. PBG is known as Electron Band Gap (EBG) in electromagnetic application. They are actually artificial periodic structures that can give metamaterial behavior.

Different DGS geometries : (a) dumbbell-shape (b) Spiral-shaped (c) H-shaped (d)U-shaped (e) arrow head dumbbell (f) concentric ring shaped (g) split-ring resonators (h)interdigital (i) cross-shaped (j) circular head dumbbell (k) square heads connected with U slots (l)open loop dumbbell (m) fractal (n)half-circle (o) V-shaped (q) meander lines (r) U-head dumbbell(s) double equilateral U (t) square slots connected with narrow slot at edge.

DESIGN METHODOLOGY

• The software simulation includes the designing of conventional antennas and DGS metamaterial antennas

• CST Studio software is used for antenna simulation.

Characteristics of substrate values

Permittivity εr 3.00 ± 0.04

Permeability, μr 1.00

Loss tangen, tan 𝛿 0.0013

Thickness, h 0.5mm

Copper cladding, t 0.035mm

Two DGS structures have been designed. The first design (a) is the circular rings and the second design (b) is the split rings.

Bottom view of DGS structures: (a) circular rings behave as metamaterial at 4.75GHz, (b) split rings behave as metamaterial at 2.45 GHz.

(a) (b)

Relative permittivity, εr and permeability, μr value versus frequencies for substrate with circular rings DGS

NRW calculation

Permittivity, εr and permeability, μr value versus frequencies for substrate with slip rings DGS.

NRW calculation

Designing rectangular patch antenna

The simulation of conventional antenna is designed for the purpose of comparison to DGS oneTwo conventional MPA antennas were designed at 4.75 GHz and 2.4 GHz respectively.Characteristics goals of conventional rectangular patch antenna

Frequency of operation 4.7 GHz and 2.4 GHz

Return loss (dB) <-10dB

Feeding method Microstrip line

Polarization Linear

FABRICATION PROCESS

• The fabrication process involves 5 steps which are:

• Generate mask on transparency film

• Photo exposure process

• Etching in developer solution

• Etching in Ferric Chloride

• Soldering the probe.

EXPECTED RESULTof 4.75 GHz antenna

• Comparison between conventional and DGS antenna performance in term of return loss, bandwidth and radiation pattern.

• that metamaterial antenna can reduce the of rectangular patch antenna SIZE

• The rectangular patch antenna with DGS gives better return loss

• that DGS antenna MAY increase the bandwidth by 60 -80 % directivity will decrease

• total efficiency will increase more than 60%

the simulation and measurement of 4.75 GHz antenna and2.45 GHz antenna is under process With the help of comparison Simulation Graph between return loss and frequency 3D radiation pattern comparisonPolar plot comparison For both antenna accurate results can be achieved .

CONCLUSION

• the dimension of a microstrip patch antenna operating at 4.7 GHz had been can be reduced up to approx. 30% of the original dimension while having larger bandwidth.

• Moreover, 2.45GHz metamaterial antenna will able to reduce the size upto 60% but having poor performance.

• the reflection coefficient reduced and

• The antennas fabricated will have better performance to the conventional one

REFERENCE[1] Pozar, D.M. Microstrip antennas.

[2] M.I.A. Khaliah, “ Electromagnetic Band Gap (EBG) for Microstrip AntennaDesign”, Master of Engineering (Electrical –Electronic Telecommunication)

[3] Ahmed A. Kishk, “Fundamentals of Antennas”, Center of Electromagnetic

[4 ] Microstrip and printed antennas, new trends technique and application