Investigation of Low Profile Antenna Designs for Use in Hand-Held Radios

Antennas in hand-held radios must be compact and unobtrusive. Electrically small and low-profile antennas experience high input reactance, low input resistance, and low radiation efficiency.Further degradation of radiation efficiency occurs in hand-held radios due to size-reduced ground planes, losses within the plastic device casing, and losses due to coupling with the tissue of the user. These factors may also affect the radiation pattern of the antenna. This discussion reports on antenna designs that are well suited for hand-held radios. The design issues are covered for electrically small antennas and the hand-held environment. A review of Microstrip Antenna (MSA) theory, and the theory of the Inverted-L Antenna (ILA), and variations on the ILA including the Inverted-F Antenna (IFA), Planar Inverted-F Antenna (PIFA), and Dual Inverted-F Antenna (DIFA) is included. Two specific antenna designs are presented: the DIFA and the Proximity-Coupled Rectangular Patch MSA. The radiation patterns and input impedance of the DIFA are calculated numerically and measured empirically. The Proximity-Coupled Rectangular Patch Microstrip Antenna is treated numerically.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1997

Author dc:creator

• Gobien, Andrew Timothy III

Chair dc:contributor.committeechair

• Stutzman, Warren L.

Committee members dc:contributor.committeemember

• Davis, William A.
• Safaai-Jazi, Ahmad

• Antennas
• Small Antennas
• Low Profile
• Hand-Held
• Inverted-F
• Microstrip

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-7697-21043

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/36959