USINGMETAMATERIALS

GAIN AND DIRECTIVITY ENHANCEMENT IN PATCH

ANTENNA

OUR TEAM

Pawan Bharti

Raunak Kumar Ritesh Kumar Shashi Shekhar Vishal Agrawal

PROJECT GUIDEDr. ANJU PRADEEP 2

● Metamaterials● Reference Papers● Simulations

OVERVIEW

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METAMATERIALS

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Metamaterial is an arrangement of periodic structures of unit cells in which the average size of a unit cell should be much smaller than the impulsive wavelength of the light.

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It was seen that wave propagation in metamaterial was in opposite direction than the naturally occurring materials. Materials with negative permittivity such as ferroelectrics were available in nature but materials with negative permeability did not exist in nature.

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For simultaneous change of sign of permittivity and permeability, the direction of energy flow is not affected..For left-handed system, n is negative, thus the phase velocity is negative. Hence the direction of energy flow and the wave will be opposite resulting in backward wave propagation

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For right handed system, n is positive, thus the phase velocity will be positive. Therefore, energy and wave will travel in same direction resulting in forward wave propagation

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Classified on the basis of Permittivity and Permeability

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Artificial Dielectrics

Artificial dielectrics are the structures having negative permittivity but positivepermeability.An array of cylinders displays negative permittivity below plasma frequency

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Artificial MagneticsArtificial magnetics are the structures having negative permeability but positivepermittivity.Artificial magnetics exhibits negative permeability below plasma frequency.

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Negative-Index MaterialThe materials with simultaneous negative permittivity and permeability are called Negative-index materials (NIM).These are also called left handed materials.The combination of alternating layers of thin metallic wires and circular split rings, Omega shaped, S shaped structures , Double H shaped structures etc. exhibits negative index of refraction.

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The combination of alternating layers of thin metallic wires and circular split rings, Omega shaped , S shaped structures etc. exhibits negative index of

refraction.

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NZIM Near Zero Index Material

CATEGORYepsilon-near-zero and mu-very-large media

mu-near-zero (MNZ) & epsilon-very-large (EVL) media

double-zero media (DZR)

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SNELL’S LAW

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Reference Paper 1

Gain Enhancement of Microstrip Patch Antenna using Near-zero Index Metamaterial (NZIM) Lens

Hemant Suthar

Debdeep Sarkar

Kushmanda Saurav

Kumar Vaibhav Srivastava

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Reference Patch Antenna

Schematic diagram of coax fed microstrip patch antenna: (a) Top view. (b) Side view; Lp= 16.5 mm,

W p= 12.6 mm, Ls= 60 mm, Ws= 50mm,

Coaxial Feed

Operation Frequency 5.2 Ghz

Impedance bandwidth of 4.25% (5.08 GHz - 5.3 GHz)

Peak realized gain of 5.6 dBi.

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Unit Cell

NZIM unit cell: (a) Top surface, (b) Bottom surface;ax= ay=4.5 mm, L1 = 4.2 mm, L2 = 1.725 mm, L3 = 1.2 mm W1 = 4.3 mm, W2 = 3.5 mm, W = 0.25

mm.

Structure printed on both sides

Substrate FR4 thickness 0.8mm

It’s a NZIM near zero index material

Enhances the gain of the reference antenna 7.65dB 20

Patch antenna with

NZIM superstrate

Height of superstrate = 35 mm

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Extracted real and imaginary part of refractive index for the proposed NZIM unit

cell

|S11| v/s frequency for the reference patch antenna and proposed antenna with single

layer NZIML. (b) Gain v/s frequency

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Extracted real and imaginary part of permittivity and permeability for the

proposed NZIM unit cell

Simulated radiation pattern of reference patch antenna and patch antenna loaded with single layer NZIML (a) E-plane. (b) H-

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Reference Paper 2

A Compact Gain Enhancement Patch Antenna Based On NZIM Superstrate.

Jinxin li

Tayab A

Qingsheng Zeng

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Reference Patch Antenna

Schematic diagram of coax fed microstrip patch antenna: Top view and side view ; L= 59.7 mm, W =

39.8 mm, Ls= 150mm, Ws=150mm, hs=12mm.

Coaxial Feed

Operation Frequency 2.44 Ghz

Impedance bandwidth of 3.25% (2.42 GHz - 2.46 GHz)

Peak realized gain of 2.3 dBi.

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● This structure is designed to act as near zero refractive index metamaterial at 2.44 GHz

● Superstrate diagram

● Unit cell diagram

NZIM UNIT CELL DESIGN

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STRUCTURE UNIT CELL AND SUPERSTRATEUnit-cell dimension of unit cell:

● a= 140mm, b= 105mm

● Length of each side of unit cell is 35mm.

● The thickness of layer is 1.575 mm.

● Substrate is RT/duroid 5880 (εr= 2.2).

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Patch Antenna Based On NZIM Superstrate

• Compact high-gain patch antenna based on near-zero index metamaterial (NZIM) superstrate lens operating at 2.44 GHz is proposed.• A single layer NZIM superstrate with unit-cell periodicity of 3 × 4 is designed and suspended above a patch antenna at a very close distance of 0.097 λ.• The proposed single layer NZIM superstrate provides a gain enhancement of 2.3 dB at 2.44 GHz to a conventional patch antenna.

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Refractive index enhancement respect to the frequency.

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● Simulation results show that the NZIM superstrate could converge the electromagnetic wave radiated by the antenna to enhance the radiation gain

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Reference Paper 3

Microstrip Antenna Gain Enhancement by Metamaterial Radome with More Subwavelength Holes

Kai-Shyung Chen,

Ken-Huang Lin,

Hsin-Lung Su

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JERUSALEM CROSS STRUCTURE UNIT CELL

•This structure is designed to act as near zero refractive index metamaterial at 3.5 GHz.

•Unit cell diagram:

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JERUSALEM CROSS STRUCTURE UNIT CELL

Unit-cell dimension of Jerusalem unit cell:

• a = 23 mm, b = 20 mm, c = 19 mm,

•d = 1mm. The thickness of each layer is 0.8 mm.

•Substrate is FR4 (εr= 4.4).

•the separation between each layer is 1.6mm.

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JERUSALEM CROSS STRUCTURE UNIT CELL

•Oprerating mechanism:

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JERUSALEM CROSS STRUCTURE UNIT CELL

•A large number of positive and negative charges assemble in the ends of the metal strip.

•it would cause the E-field that is distributed as shown in Figure.

•E-field distribution phenomenon would form a vortex to collect the electromagnetic wave and collimate the electromagnetic wave passing through this subwavelength hole

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JERUSALEM CROSS STRUCTURE UNIT CELL

Refractive index enhancement

respect to the frequency

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PATCH ANTENNAPATCH ANTENNA DIMENSION:19.6mm*19.6mmThickness of substrate=1.6mmGround plane =69mm*69mmOperating frequency=3.5GHzPeak gain of patch antenna =4.39DBi

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JERUSALEM CROSS STRUCTURE UNIT CELL

Gain and directivity enhancement of the patch antenna using The Jerusalem structure metamaterial radome which has 9 holes and 4 holes. 39

Reference Paper 4

BROADSIDE GAIN AND BANDWIDTH ENHANCEMENT OF MICROSTRIP PATCH ANTENNA USING A MNZ-METASURFACE

KWOK L. CHUNG

SARAWUTH CHAIMOOL

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Unit-cell and 4 4 cells (p = 20, L1 = 18, L2 = 16, d = 1, unit: mm)

UNIT CELL

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Side view of the metasurfaced patch antenna (h1 = 1.6, h2 = 6.0,

h3 = 0.8, unit: mm, FR4: P1 = P3 = 4.2) and top view of the patch only (L = 28, W = 29, unit: mm)

Side View

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Photograph of the source patch and the MNZ- metasurface.

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SIMULATIONS

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PATCH ANTENNA

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RADIATION PATTERN 3-D

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UNIT CELL [DOUBLE ‘S’]

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S21 parameter

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S11 parameter

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Thank you !!

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