Miniaturization and Gain Enhancement of Wideband Low-profile Antennas on Engineered Structures

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• Miniaturization and Gain Enhancement of Wideband
  Low-profile Antennas on Engineered Structures
• Presented by -
• Faisal Abedin
• (Doctoral Candidate)
• Department of Electrical Engineering
• University of South Carolina, Columbia, SC 29208
• E-mail abedin_at_engr.sc.edu
• Advisor Dr. Mohammod Ali

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Biography

• Education
• Doctoral Candidate (GPA 3.92)
• Major Electrical Engineering (Start Date
  Spring 2003)
• Department of Electrical Engineering
• University of South Carolina, Columbia, SC
• M.S. in Electrical Engineering, May 2001
• Department of Electrical and Computer
  Engineering
• North Carolina State University, Raleigh, NC
• B.S. in Electrical Engineering, September 1999
• Department of Electrical Engineering
• Bangladesh University of Engineering and
  Technology, Dhaka, Bangladesh
• Research Interest
• Electromagnetic Band-gap (EBG) Structures and
  their Antenna Applications
• Antenna miniaturization
• Diversity antennas

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Outline

• Introduction
• Novel concept to design ultra-thin Mobile Phone
  Antennas
• Introduction to Engineered Structures called
  Electromagnetic Bandgap (EBG) structures
• Three-dimensional EBG structures
• Planar EBG structures
• Phase profile of EBG structures
• Application of Planar EBG structures

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Introduction
Personal Communication Systems
Commercial Defense Applications
UAV
Satellite
Mobile Data System
GPS
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Novel Design Concept for Mobile Antennas
Application Mobile Antennas
Dual band antenna on Modified ground plane
Dual band antenna on Conventional ground plane
Proposed a Novel Slow-wave Structure
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Novel Design Concept for Mobile Antennas

• Accomplishments
• Increases the antenna electrical length by
  uniformly spreading current
• Increases the antenna bandwidth by 3 to 4 times
• Reduces the antenna height by 2.5 times

M. F. Abedin and M. Ali, Modifying the Ground
Plane and its Effect on Planar Inverted-F
Antennas (PIFAs) for Mobile Phone Handsets,
IEEE Antennas and Wireless Propagation Letters,
vol.2, no. 15, pp. 226-229, 2003.
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Antenna Miniaturization using Engineered
Structures

• Applications of Dipole Antenna Array
• Ground-based
• Vehicular
• Air-borne applications

UAV
Conventional Dipole Array Configuration
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Antenna Miniaturization using Engineered
Structures
Proposed Solution
Engineered Structure (EBG)

• Thin antenna structure
• Light-weight and compact
• Directional
• Wideband

Goals
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Antenna Miniaturization using Engineered
Structures
Phase Profile of EBG Structures
Phase profile
Phase (Degrees)
Frequency (GHz)
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Antenna Miniaturization using Engineered
Structures
Dipole Antenna Performance on Proposed EBG
Structure
Reflection (decibels)
EBG Top View

• Accomplishments
• Reduced antenna height by 9 times
• Attained sufficient antenna bandwidth
• Increased antenna Gain and Efficiency

M. F. Abedin and M. Ali, Effects of EBG
Reflection Phase Profiles on the Input Impedance
and Bandwidth of Ultra-thin Directional
Dipoles, IEEE Transactions on Antennas and
Propagation (under revision).
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Novel Planar EBG Structures
Applications Planar EBG ? Mobile phones ?
Wireless LAN ? Satellite ? JTRS ? Global
Positioning System
Unit cell of proposed Planar EBG Structure
Top-view
Advantages Planar EBG ? Extremely low cost ?
Easy to fabricate
Transmission (decibels)
Stopband 3.5 4.5 GHz
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Application of Planar EBG Structures
Mutual Coupling (decibels)
Coupling reduced by 13 dB
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Application of Planar EBG Structures
Without EBG
With EBG
Nulls Eliminated
Null Points No Signal

• Accomplishments
• Increased bandwidth by 31
• Reduced coupling by 13 dB
• Eliminated Nulls in Radiation Pattern
• Increased antenna Gain

M. F. Abedin and M. Ali, Application of EBG
Structures to Reduce the Mutual Coupling between
Linear Antenna Elements of an Array, IEEE
Antennas and Wireless Propagation Letters
(submitted March 2005).
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Broader Dissemination

• Actively involved in disseminating knowledge to
  the broader community
• Mentored two High School Seniors through SPRI
  program in previous years
• This summer an 11th Grade student will be
  mentored to conduct research
• An undergraduate EE student of USC will be guided
  this summer funded through an NSF REU grant

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Relevant Publications

1. M. F. Abedin and M. Ali, Modifying the Ground
   Plane and its Effect on Planar Inverted-F
   Antennas (PIFAs) for Mobile Phone Handsets,
   IEEE Antennas and Wireless Propagation Letters,
   vol. 2, no. 15, pp. 226-229, 2003.
2. M. F. Abedin and M. Ali, Effects of EBG
   Reflection Phase Profiles on the Input Impedance
   and Bandwidth of Ultra-thin Directional
   Dipoles, IEEE Transactions on Antennas
   Propagation (under revision).
3. M. F. Abedin and M. Ali, Application of EBG
   Structures to Reduce the Mutual Coupling between
   Linear Antenna Elements of an Array, IEEE
   Antennas and Wireless Propagation Letters
   (submitted).
4. M. Ali and M. F. Abedin, Designing Ultra-Thin
   Planar Inverted-F Antennas, in Proc. IEEE
   Antennas and Propagation Society International
   Symposium Digest, vol. 3, pp. 78-81, Columbus,
   OH, June 2003.
5. M. F. Abedin and M. Ali, Application of EBG
   Substrates to Design Ultra-Thin Wideband
   Directional Dipoles, in Proc. IEEE Antennas and
   Propagation Society International Symposium, vol.
   2, pp. 2071-2074, Monterey, CA, June 2004.
6. M. F. Abedin and M. Ali, Designing Ultra-Thin
   Printed Dipole Arrays based on EBG Reflection
   Phase Profile, IEEE Wireless and Microwave
   Technology (WAMI) Conference 2005, Clearwater,
   FL, April 2005 (accepted).
7. M. F. Abedin and M. Ali, Reducing the
   Mutual-Coupling between the Elements of a Printed
   Dipole Array Using Planar EBG Structures, IEEE
   Antennas and Propagation Society International
   Symposium, Washington, DC, July 2005 (submitted).
8. M. F. Abedin, M. Ali and P. F. Wahid, Bandwidth,
   Efficiency and Pattern Characteristics of
   Miniaturized Embedded Antennas at 900/1900 MHz,
   9th edition of the Biennial International
   Conference on Electromagnetics in Advanced
   Applications.(ICEAA 2005), Torino, Italy,
   September 2005 (under preparation).

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