Metamaterial used in the papers were NZIM near-zero refractive index

1. USING
METAMATERIALS
GAIN AND DIRECTIVITY
ENHANCEMENT IN PATCH
ANTENNA

2. OUR TEAM
Pawan Bharti Raunak Kumar Ritesh Kumar Shashi Shekhar Vishal Agrawal
PROJECT GUIDE
Dr. ANJU PRADEEP
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3. ● Metamaterials
● Reference Papers
● Simulations
OVERVIEW
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4. METAMATERIALS
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5. 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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6. 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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7. 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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8. 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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9. Classified on the basis of
Permittivity and Permeability
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10. Artificial Dielectrics
Artificial dielectrics are the
structures having negative
permittivity but positive
permeability.
An array of cylinders displays
negative permittivity below
plasma frequency
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12. Artificial Magnetics
Artificial magnetics are the
structures having negative
permeability but positive
permittivity.
Artificial magnetics exhibits
negative permeability below
plasma frequency.
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13. Negative-Index Material
The 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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15. 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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16. NZIM
Near Zero Index Material
CATEGORY
epsilon-near-zero and
mu-very-large media
mu-near-zero (MNZ) &
epsilon-very-large (EVL)
media
double-zero media (DZR)
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17. SNELL’S LAW
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18. 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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19. 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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20. 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
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21. Patch antenna with
NZIM superstrate
Height of superstrate = 35 mm
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22. 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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23. 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-plane.
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24. Reference Paper
2
A Compact Gain Enhancement Patch
Antenna Based On NZIM Superstrate.
Jinxin li
Tayab A
Qingsheng Zeng
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25. 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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26. ● 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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27. STRUCTURE UNIT CELL AND SUPERSTRATE
Unit-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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28. 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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29. Refractive index
enhancement respect
to the frequency.
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30. ● 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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31. 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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32. 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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33. 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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34. JERUSALEM CROSS STRUCTURE UNIT CELL
•Oprerating mechanism:
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35. 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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36. JERUSALEM CROSS STRUCTURE UNIT CELL
Refractive index enhancement
respect to the frequency
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37. PATCH ANTENNA
PATCH ANTENNA DIMENSION:
19.6mm*19.6mm
Thickness of substrate=1.6mm
Ground plane =69mm*69mm
Operating frequency=3.5GHz
Peak gain of patch antenna =4.39DBi
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39. 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.
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40. Reference Paper
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BROADSIDE GAIN AND
BANDWIDTH ENHANCEMENT
OF MICROSTRIP PATCH
ANTENNA USING A MNZ-
METASURFACE
KWOK L. CHUNG
SARAWUTH CHAIMOOL
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41. Unit-cell and 4 4 cells (p = 20, L1 = 18, L2 = 16, d = 1, unit: mm)
UNIT CELL
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42. 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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43. Photograph of
the source patch
and the MNZ-
metasurface.
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47. SIMULATIONS
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48. PATCH ANTENNA
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51. RADIATION PATTERN 3-D
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52. UNIT CELL [DOUBLE ‘S’]
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53. S21 parameter
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54. S11 parameter
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55. Thank you !!
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