This document discusses the miniaturization of various slot antennas. It examines microstrip-fed straight slot antennas, CPW-fed slot antennas, and CPW-fed slot loop antennas loaded with inductive elements. The antennas were simulated using HFSS software. Miniaturization was achieved through loading slots with strips and inductive slits, which reduced the resonance frequency by up to 37.57%. Future work aims to improve radiation patterns and efficiency.

1. Dinesh Kumar Kalotra(MU11EC04)
Sabyasachi Choudhury(MU11EC16)
Under the Guidance of Mr. Abhishek Sarkhel
Department of Electronics and
Communication Engineering
National Institute of Technology Meghalaya
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2.  Introduction
 Miniaturization micro strip feed slot antenna
 Miniaturization CPW feed slot antenna
 Miniaturization CPW feed slot loop antenna
 Conclusion
 Future Work
 References
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3.  Antenna is open circuit transmission line where the time
varying chargers are present at its aperture and is going to
produce radiation at far field
 Types of antennas Dipole, Micro-strip patch, Parabolic dish
antennas
 Miniaturization of antenna
 Antennas real estate should be compactable with the portable
device
 In our presentation we are mainly going to focus on slot
antenna
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4. Geometry of a Micro strip-Fed Straight
Slot Antenna
Geometry of a Micro strip-Fed
Straight Slot Antenna Loaded
With an Array of Series
Inductive Elements.
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5. The slit length is less than λg/4
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6.  Low loss Compared to Micro-strip Feed
 Uniplanar Configuration
 Avoid Drilling in Antenna as Required With Coax Feed
 Do not Need Vias
Inductive Feed Capacitive Feed Square Feed Circular Feed
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7. • The CPW fed slot antenna is designed at 3.4GHz with the symmetrical structure, as
shown in figure(1)
• This antenna has a substrate with thickness (H) of 1.575mm and dielectric
constant( ) of 2.2
• The coplanar waveguide (CPW) is designed to be 50 ohms in order to match the
characteristic impedance of transmission line. The dimension of the slot antenna is
referred to the guide wavelength of the slot which given by
where is an effective dielectric constant
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e
(l g)
CPW Feed Slot Antenna
Figure(1)

8. Basic CPW Feed Slot Antenna Return loss( Simulated )
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The length of slot is λg/2
The S11 deep suggest the
maximum point of
impedance matching

9. CPW Feed Slot Antenna
With Both Sides Slits
Return Loss ( Simulated )
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10. Impedance Plot of CPW Feed
Slot Antenna
Impedance Plot of CPW Feed Slot
Antenna With Both Side Slits
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11. E plane Radiation Pattern of CPW Feed
Slot Antenna With Both Side Slits
E plane Radiation Pattern
of CPW Feed Slot Antenna
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12. Return Loss of Basic CPW Feed Slot Antenna & of CPW Feed Slot Antenna
With Both Sides Slits
 Reduction in resonance frequency 37.57%
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13. Simulated structure of slot loop antenna using HFSS
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14. Simulated S11 plot using HFSS
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15. Simulated Structure of slot loop antenna
using inductive slit loading using HFSS
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16. Simulated S11 plot using HFSS
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17. Simulated E-plane and H-plane radiation
pattern using HFSS
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18. Slot loop antenna can be miniaturized by using
the inductive slit loading technique.
Dimension of the loaded slit and nature of the
substrate can be used to vary the impedance
matching.
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19. • To improve the radiation pattern of the slit
loaded antenna and to increase the efficiency
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20. [1] K.Sarabandi,“Bandwidth Enhancement and further size reduction of a class of miniaturized
Slot Antennas” IEEE Trans. Antennas Propagat., vol.52, No. 8 August 2004
[2] B.Ghosh, SK. Moinul Haque, and Sebasis Mitra“Miniaturization of slot Antennas Using slit
and Strip loading” IEEE Trans. Antennas Propagat., vol.59, No.10 October 2011
[3] You-Chieh Chen “A Modified CPW-Fed Slot Loop Antenna With Reduced Cross Polarization
and Size” IEEE Trans. Antennas Propagat., vol.10,2011
[4] John D. Kraus Antenna and wave propagation
[5] Ansoft HFSS 15.0
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21. ECE DEPT. NIT MGH