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On-body Antenna Design using Carbon
Nanotubes
Centre for Electromagnetic and Antenna Engineering (CELANE) Department of Engineering
Presenter: Syed Muzahir Abbas, Ph.D. Student
Supervisor: Prof. Karu Esselle
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Presentation Outline • Project Overview
• Background
– Antennas
– CNT
– CNT Yarns
– Body Centric Communication
– On-body Antennas
• Research Objectives
– On-body Antenna Design Requirements
– Design Constraints/Aims & Objective
– Expected Outcomes
• Task Plan
• Conclusion
4/28
Presentation Outline • Project Overview
• Background
– Antennas
– CNT
– CNT Yarns
– Body Centric Communication
– On-body Antennas
• Research Objectives
– On-body Antenna Design Requirements
– Design Constraints/Aims & Objective
– Expected Outcomes
• Task Plan
• Conclusion
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Antennas [1] • Antenna Definition
“Usually a metallic device (as a rod or wire) for radiating or receiving radio waves”. (Webster’s dictionary)
OR
“A means for radiating or receiving radio waves”. (IEEE Standard)
• Antenna Parameters
– Antenna Impendence
– Efficiency
– Radiation Pattern
– Antenna Gain
– Directivity
– Antenna Polarization
– Bandwidth
– Return Loss
[1] C. A. Balanis, Antenna Theory: Analysis and Design: John Wiley, 2005.
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Carbon Nanotube (CNT) • Potential candidates for replacement of
conventional metals – Density of CNT composites is about five time lower
than copper and around half that of aluminium.
– Thermal conductivity is about ten times that of copper
• Significant Advantages – Mechanical (high strength and load bearing)
– Electrical (conductivity and resistivity)
– Thermal (sustain at high temperatures)
– Non-oxidizing abilities
• Applications – Nanoantennas
– Nanoelectronics
• Allotropes of carbon with a cylindrical nanostructure
Fig. 1: Diamond *
Fig. 2: Graphite *
* http://chem-guide.blogspot.com.au/2010/04/covalent-solid.html
Graphene
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Carbon Nanotube (CNT) -- Continued
• CNT can be categorized as
– Single-Walled Carbon Nanotube (SWCNT)
A layer of graphite, a single atom thick, called graphene, which is rolled into a seamless cylinder
Diameter is close to 1nm
Length thousand times of diameter
– Multi-Walled Carbon Nanotube (MWCNT)
Consist of concentric tubes (i.e. multiple rolled layers) of graphene. OR
As a single sheet of graphite rolled into the shape of a scroll.
Diameter range is 5nm to 50nm
Length thousand times of diameter
Fig. 3: SWCNT *
Fig. 4: MWCNT *
*http://staff.aist.go.jp/h-kataura/Kogaku-kiji-forweb.htm
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Carbon Nanotube (CNT) -- Continued
Fig. 5: Carbon Nanotubes *
* http://explow.com/buckypaper http://www.phy.mtu.edu/yap/frontiercarbon.html
a b
c d
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CNTs in Antenna Applications -- Continued
– Polymer-carbon nanotube sheets for conformal load bearing antennas.
– Presented circuit model to calculate CNT sheet conductivity.
– Presented fabrication process.
• Load Bearing Antenna Applications [2]
Fig. 6: Circuit model for conductivity [2]
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CNTs in Antenna Applications -- Continued – Conducted mechanical tests for
• Stress,
• Strain
• Bending
Fig. 7: (a) Stress (b) Strain (c) Bend [2]
[2] Z. Yijun, Y. Bayram, D. Feng, D. Liming, and J. L. Volakis, "Polymer-Carbon Nanotube Sheets for Conformal Load Bearing Antennas," Antennas and Propagation, IEEE Transactions on, vol. 58, pp. 2169-2175, 2010.
– Proposed it suitable for conformal load bearing antennas and RF circuits.
(b)
(c)
(a)
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CNTs in Antenna Applications -- Continued
– Full-Composite Fractal Antenna Using Carbon Nanotubes for Multiband Wireless Applications.
– UHF-RFID (900MHz), Blutooth (2.4GHz) and WLAN (5.5GHz).
– Presented antenna design and fabrication process.
– Antenna gain and read range can be controlled by changing the conductivity of composite, which is not possible for materials with fixed conductivity such as copper.
• Multiband Wireless Applications [3]
Fig. 8: Fractal Antenna Design [3]
[3] A. Mehdipour, I. D. Rosca, A. R. Sebak, C. W. Trueman, and S. V. Hoa, "Full-Composite Fractal Antenna Using Carbon Nanotubes for Multiband Wireless Applications," Antennas and Wireless Propagation Letters, IEEE, vol. 9, pp. 891-894, 2010.
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CNTs in Antenna Applications -- Continued
– Comparison of copper and CNT antennas.
– Frequency range 24 - 34 GHz.
– Presented antenna design and fabrication process.
– Housing effect on the performance of CNT antenna is much lower than for the copper antenna
– Above 30GHz its significantly less resulting in stable gain and less distortion in radiation pattern.
• Wideband Millimeter-Wave Antenna Applications [4]
Fig. 9: (a) Antenna Design (b) Array [4]
[4] A. Mehdipour, I. D. Rosca, A. R. Sebak, C. W. Trueman, and S. V. Hoa, "Carbon Nanotube Composites for Wideband Millimeter-Wave Antenna Applications," Antennas and Propagation, IEEE Transactions on, vol. 59, pp. 3572-3578, 2011.
(a)
(b)
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Carbon Nanotube (CNT) Yarns • CNT yarns (fibers) are composed of individual CNTs
• Can be spun from CNT forest by spinning
• By passing CNT films through a drop of volatile liquid
Fig. 10: CNT yarns production by CSIRO*
* http://www.csiro.au/Outcomes/Materials-and-Manufacturing/ Innovation/Carbon-Nanotubes-2.aspx
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Body Centric Communication [5]
• Off-body communication
– Communications from off-body to an on-body device or system
• On-body communication
– Communications within on-body networks and wearable systems
• In-body communication
– Communications to medical implants and sensor networks
Fig. 11: Human body model
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Presentation Outline • Project Overview
• Background
– Antennas
– CNT
– CNT Yarns
– Body Centric Communication
– On-body Antennas
• Research Objectives
– On-body Antenna Design Requirements
– Design Constraints/Aims & Objective
– Expected Outcomes
• Task Plan
• Conclusion
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On-body Antenna Design Requirements
• Frequency Range
– UWB lower band (3 - 5 GHz)
– UWB (3.1 – 10.6 GHz)
– V-Band (7 GHz around 60 GHz)
TABLE: Unlicensed frequency bands around 60 GHz [6].
• Antenna Impedance
– 50 ohm
Country Japan USA Canada Korea Europe Australia
Frequency Band (GHz)
59-66 57.05-64 57-64 57-64 57-64 59.4-62
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Design Constraints/Aims & Objective
• Polarization
– Horizontal / Vertical
• Radiation Pattern [6]
– Omni-directional and along the body surface
• Full Ground Plane
– To prevent radiation towards body
• Bandwidth
– Larger bandwidth
• Size/Weight
– Small/Light
• Distance b/w antenna and body
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Expected Outcomes
• RF/Microwave characterization of CNT yarns
• Antenna prototype for on-body communication with desired parameters
• Which polarization is suitable and why?
• Desired radiation pattern over the required bandwidth
• How bandwidth can be enhanced in presence of full ground plane?
• Recommended distance between antenna and body?
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Presentation Outline • Project Overview
• Background
– Antennas
– CNT
– CNT Yarns
– Body Centric Communication
– On-body Antennas
• Research Objectives
– On-body Antenna Design Requirements
– Design Constraints/Aims & Objective
– Expected Outcomes
• Task Plan
• Conclusion
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Task Plan-First year (2012-2013) Months 1 - 6 7 - 8 9 - 11 12
Task-1, Literature Review Mar –Aug2012
Task-2, Software Learning Sep-Oct
Task-3, Test Structures Designing Nov-Jan2013
Task-4, Test Structures Fabrication Feb
Task-1, Literature Review (6-months)
– To strengthen the relevant knowledge and to gain detailed insight of existing work carried out so far in the field under investigation
– CNT, CNT yarns, Antennas, On-body communication/antennas, UWB, Human body properties
Deliverables
– Literature review report
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Task Plan-First year (2012-2013)
Task-2, Software Learning (2-months)
– High Frequency Structure Simulator (HFSS) Completed
– CST Microwave Studio In progress
– AWR Microwave Office In progress
Tasks To Do
– Task-3, Test Structures Designing
– Task-4, Test Structures Fabrication
Task-1, Achieved (March 2012 to date)
– CNT, CNT yarns, Antennas, On-body communication/antennas, UWB, Human body properties
Deliverables
– Test Structures
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Task Plan-Second year (2013-2014)
Months 13 - 15 16 - 18 19 - 21 22-24
Task-5, CNT Measurements Mar –May2013
Task-6, Antenna Designing Jun-Aug
Task-7, Antenna Simulations Sep-Nov
Task-8, Antenna Fabrication Dec
Task-9, Antenna Testing Jan-Feb2014
Deliverables
– Properties of CNT yarns
– Antenna prototype
– Publication of results in International conferences/journals
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Task Plan-Third year (2014-2015)
Months 25 - 26 27 - 36
Task-10, Results and Analysis Mar-Apr2014
Task-11, Write-up May2014 - Feb2015
Deliverables
– Publication of results in International conferences/journals
– Thesis write-up
– Completion of thesis in 3 years
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Presentation Outline • Project Overview
• Background
– Antennas
– CNT
– CNT Yarns
– Body Centric Communication
– On-body Antennas
• Research Objectives
– On-body Antenna Design Requirements
– Design Constraints/Aims & Objective
– Expected Outcomes
• Task Plan
• Conclusion
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Conclusion
• Overview of CNT, CNT yarns, body-centric communication, on-body antennas
• Use of CNTs in antenna applications and their advantages
• On-body antenna design requirements
• Design Constraints/Aims & Objective
• Expected outcomes
• Task plan (achieved & to do)
• Investigating RF/Microwave characterization of CNT yarns will open new dimensions for their usage in nanoantennas and nanoelectronics applications
• CNT based antennas for on-body communications will be compact, light weight, flexible and will have better performance characteristics
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References [1] C. A. Balanis, Antenna Theory: Analysis and Design: John Wiley, 2005.
[2] Z. Yijun, Y. Bayram, D. Feng, D. Liming, and J. L. Volakis, "Polymer-Carbon Nanotube Sheets for Conformal Load Bearing Antennas," Antennas and Propagation, IEEE Transactions on, vol. 58, pp. 2169-2175, 2010.
[3] A. Mehdipour, I. D. Rosca, A. R. Sebak, C. W. Trueman, and S. V. Hoa, "Full-Composite Fractal Antenna Using Carbon Nanotubes for Multiband Wireless Applications," Antennas and Wireless Propagation Letters, IEEE, vol. 9, pp. 891-894, 2010.
[4] A. Mehdipour, I. D. Rosca, A. R. Sebak, C. W. Trueman, and S. V. Hoa, "Carbon Nanotube Composites for Wideband Millimeter-Wave Antenna Applications," Antennas and Propagation, IEEE Transactions on, vol. 59, pp. 3572-3578, 2011.
[5] P. S. Hall and Y. Hao, Antennas and propagation for body-centric wireless communications: Artech House, 2006.
[6] A. Brizzi, A. Pellegrini, and Y. Hao, "Design of a cylindrical resonant cavity antenna for BAN applications at V band," in Antenna Technology (iWAT), 2012 IEEE International Workshop on, 2012, pp. 152-155.
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