Post on 24-Dec-2015
transcript
Enhancement of Tools for Design of Antennas for Mobile Devices
2003 Clemson SURE Program
Presented By: Robert J. Loeven
Advisor: Dr. Anthony Martin
Modern Mobile Device Antennas Very Small Multi-Band Used in Cell Phones,
Wireless Laptops, etc. PIFA – Planar Inverted
F-type Antenna
Project Goals
Use MATLAB to model antenna structures and performance, using Makarov programs Antenna and EM Modeling, Sergey N. Makarov, John Wiley and Sons Inc. 2002
Alter Makarov programs to show more detail and enhance quality of output
Use new programs to analyze antennas, specifically patch antennas designed for cell phones and wireless notebook connections
Triangular Surface-Patch Meshes and the Rao-Wilton-Glisson Basis Functions First requires a 3D
“Mesh” antenna structure which can be created using MATLAB PDE Toolbox
Plate Example
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RWG1.m
RWG2.m
RWG3.m
RWG4.m
RWG5.m
AntennaMesh
Mesh1.mat
Mesh2.mat
Imedance.mat
Current.mat
These two routinesgenerally are devotedto geometry setup and
bookkeeping tasks
Fills the all-importantimpedance matrix [Z]
Solve system ofequations for the
current coefficients [I]
Displays graph of theantenna with surface
currents included
Efield1.m
Efield2.m
Efield3.m
Mesh2.mat (Antennamesh)
Current.mat (AntennaCurrent Density)
Computes thefield at a point in
space
Conputesradiation intensityU over a facetedspherical surface
Creates 2D PolarPlots
Point.m
Point.m
Point.m
Equations
Surface Currents –
Current Interpolation
( / 2 ) ( ),
( / 2 ) ( ),
0, otherwise
m m m m
m m m m m
l A T
l A T
r r
f r r r
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Bowtie Example to Demonstrate Color Modifications in RWG5.m and plotcurr5.m
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Bowtie – RWG5 - Old vs. New
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Bowtie Example – New Plotcurr5 Output
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3D Far-Field Patterns: Old Efield2.m
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New Efield3D.m with Antenna and Transparency
Efield3D.m 3D Rotation
Simulated Dipole Frequency Sweep
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x 108
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Frequency, Hz
Ref
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Dipole Frequency Demonstration λ/2 (75MHz) λ (150MHz)
3λ/2 (225MHz)
2λ (300 MHz)
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Patch Antenna Design Simulation
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Frequency Sweep Results 500 MHz to 6 GHz
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Frequency, Hz
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x 109
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Frequency, Hz
Input
resis
tance/r
eacta
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Ohm
Resistance-solid; reactance-dashed
Current Distribution at 2 GHz
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Patch Antenna E-Field
Patch E-field with Antenna Included
E-Shaped Patch Antenna Simulation
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E-Shape Analysis
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Frequency, Hz
Inpu
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Resistance-solid; reactance-dashed
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Frequency, Hz
Ret
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E-Shape Surface Currents
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E-Shape 3D E-Field
E-Shape 3D with Antenna Included
Future Work
Speed up code by using matrix interpolation
Modify plotcurr5.m code to work in 3D
Modify codes to allow for the inclusion of dielectric materials into the antennas
Use program to simulate and study real world antenna designs