Multifunctional Materials Antenna Array Team Rachel Anderson, JD Barrera, Amy Bolon, Stephen Davis,...
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Transcript of Multifunctional Materials Antenna Array Team Rachel Anderson, JD Barrera, Amy Bolon, Stephen Davis,...
Multifunctional Materials Antenna Array Team
Rachel Anderson, JD Barrera, Amy Bolon, Stephen Davis, Jamie Edelen, Justin Marshall,
Cameron Peters, David Umana
Frank Drummond, Sean Goldberger
Dr. Gregory H. Huff
Dr. Patrick Fink, Tim Kennedy, Phong Ngo Space Engineering Institute
Texas A&M University
College Station, TX 77843-3118Email: [email protected]
Team Breakdown
Materials Team– Amy Bolon, Senior
Mechanical Engineering– Stephen Davis,
Sophomore Aerospace Engineering
– Cameron Peters, Freshman Aerospace Engineering
Antenna Team– Rachel Anderson, Senior
Electrical Engineering– JD Barrera, Senior
Electrical Engineering– Jamie Edelen, Freshman
Computer Engineering– Justin Marshall, Senior
Electrical Engineering– David Umana, Freshman
Electrical Engineering
Graduate Mentors – Frank Drummond, Aerospace Engineering– Sean Goldberger, Electrical Engineering
Outline
Motivation Project Goals Methodology Materials Antennas Integrated System Results Future Work Questions
Motivation
NASA JSC Needs
Advanced airborne and space-based platforms
Antennas that utilize the electromagnetic spectrum more effectively
Operating at multiple frequencies
Communication on multiple channels
Project Goals
Investigate multidisciplinary concepts, materials, and measurements needed to simultaneously reconfigure the antenna array
Design and fabricate a 1x2 array of reconfigurable microstrip patch antennas using electromagnetically functionalized colloidal dispersions (EFCDs)
Determine the limits of reconfiguration and electromagnetic visibility of colloidal dispersions with different material systems (dielectric, magnetic, etc.)
System Diagram
Reconfigurable Antennas
Other Systems: Uses PIN diode switches or
Microelectromechanical systems (MEMS) actuator
Thermal issues
Our System: Pressure Driven Vascular
Network No Bias/Control Wires Continuous Tuning Integrated into Substrate
Reconfigurable Microstrip Parasitic Array [10]
PIN diode-based reconfigurable antenna [8]
Methodology
Examined concepts for colloidal material with electrical double layer
Perform experiments on microfluidically reconfigurable antenna array
Electromagnetically Functionalized Colloidal Dispersions (EFCDs)
Barium Strontium Titanate (BSTO)– High dielectric constant– Low losses– Availability
Oil– Low losses– Easily varied viscosity– Availability
Surfactant– Prevents material aggregation
Materials
Oil
BSTO Surfactant
Materials
Permittivity – describes how an electric field affects and is affected by a dielectric material– High permittivity reduces electric field present
Colloids – system involving small particles of one substance suspended in another– ex: milk, Styrofoam, mist
Surfactant creates the electrical double layer around the BSTO particles, which deters aggregation
[2] [3]
Electrostatics
Gauss’s Law– Assuming linear dielectric, no magnetic field– Governing equation used for modeling
Electric Fields produced by particles
eE
[5]
Calculate the effective material properties for a colloidal mixture (permittivity, permeability)
For non-ideal systems, have to consider:– Shape (spheres, discs or needles)– Heterogeneous inclusions (layered sphere)– Polydispersity (various shapes, sizes and masses)
Maxwell Garnett Mixing Rule
3
2i e
eff e e
i e i e
S SS S S
S S S S
Maxwell Garnett Mixing Rule Equation [9]
εe = 5
εi = 80
Studied the relationship between permittivity and the electric field
Greater permittivities reduces the effect of the electric field
Problem set up:– Single particle within a fluid, voltages on either end– Particle and fluid have different permittivities
Permittivity Example
εfεp
1V -1VL=1, r=0.1
Permittivity Example Results
Case 2:
εf=100ε0, εp=10ε0
Case 1:
εf=100ε0, εp=1000ε0
Model the fluid and particle flow for the antenna– Find effective properties of fluid flowing around particles
Materials Team Goal
εpεp
εp
εf
εeff
Effective Properties Calculation
Using periodic boundary conditions to solve for the effective permittivity of the colloidal fluid
Vary direction of voltage flow to solve for the electric field (E) and electric displacement (D) in the x and y directions– Solve the following equation:
Permittivity matrix is in the form of the identity matrix
y
x
y
x
E
E
D
D
2221
1211
0
0
2D COMSOL Results
f COMSOL MG % Error0.1 2.56 2.80 8.410.2 3.14 3.66 14.270.3 3.89 4.78 18.550.4 4.96 6.26 20.720.5 6.43 8.32 22.73
Voltage varying in X-direction
Voltage varying in Y-direction
50%
3D COMSOL Results
f COMSOL MG % Error0.1 2.79 2.80 0.180.2 3.67 3.66 0.200.3 4.87 4.78 1.970.4 6.79 6.26 8.53
0.45 8.47 7.20 17.70
10%
1001 1003 1005 1007 1009 1011
Fo
rce
(10-1
7N
)
120
100
80
60
40
20
0
Frequency Effects on Particle
A particle between two electrodes with AC voltage will receive a force dependent upon frequency
V
V=0
Patch Antenna Background
Substrate clad with two conductive layers
Resonant frequency based on dimensions and substrate properties
Coaxial probe used as transmission line
Lowest order mode (TE10)
Electric Distribution Radiation as a result of fringe fields
Single Patch Antenna [7] Transmission Line and Electric Field [7]
Calculations: Matlab
Equations used for very 1st order approximations Implemented equations in Matlab
Length of Patch 28.29mm
Width of Patch 36.96mm
Matlab Calculation Results Graph – Antenna Length vs. Frequency
2
2 1o
pr r
vW
f
Antenna Equations
Lf
Looeffr
p 22
1
[6]
[6]
HFSS Modeling
HFSS – Electromagnetic simulator and CAD software Simulated single patch antenna Obtain better approximations for length and probe positioning
HFSS Single Patch Antenna Model
HFSS Simulated Results
Length of Patch 27.9mm
Width of Patch 37mm
a (Distance from Edge)
5.7mm
HFSS Modeling Results1
1SWRV
VSWR plot: 1 corresponds to 100% power transmitted Water wave hitting a wall
Smith Chart: 1 corresponds to all min on VSWR Bulls eye
1
1VSWR
Current Research
Integration of Vascular Reconfiguration Mechanisms in a Microstrip Patch Antenna, G. H. Huff and S. Goldberger, in review IEEE Antennas and Wireless Propagation Letters, submitted Nov. 2007
Patch Array
Antenna Fabrication
Construct Substrate Mold Mix and Bake Substrate Solder Probes to Ground Plane
Complete Antenna Structure Solder Probe and Overlapping Copper Tape
Cut Copper Tape and Attach to Substrate
Material Preparation
Gather Materials Weigh EFCD, Surfactant and Oil
Input material into syringe
Mix Material with Vortex Machine
Place Material in Sonicator
Place syringe in system syringe pump
Reconfigurable Antenna System
Entire Reconfigurable Antenna Setup
System connected by tubing, valves and Y-splitters Inner capillary of antenna filled with oil EFCD material flows through outer capillaries of antenna
Results
Microstrip Patch Array: Experimental Model (3 GHz Design)
Results
Smith Chart VSWR Plot
(GHz)
Resonant frequency decreased 150MHz
as EFCD introduced into antenna system
Small Array Behavior of Frequency Reconfigurable Antennas Enabled by Functionalized Dispersions of Colloidal Materials , Sean Goldberger and G. H. Huff, in proc. 2009 URSI North American Radio Science Meeting, Boulder, CO, Jan. 2009
Future Work
Poly-dispersal systems Different EFCD particle
shapes Different antenna
designs Materials Feasibility testing of
system in dynamic environment
Closed loop system Zero gravity testing
NASA KC-135 [3]
Acknowledgements
Dr. Gregory H. Huff Dr. Patrick Fink Tim Kennedy Phong Ngo Dr. James G. Boyd Mrs. Magda Lagoudas Stephen A. Long Jacob McDonald Bolutife P. Ajayi Frank Drummond Sean Goldberger
References
[1] Ansoft, HFSS© v11.1.2, Pittsburgh, PA 15219 [2] "Capacitor." Chemistry Daily. 4 Jan. 2007. Oct. 2008 <http://www.chemistrydaily.com/chemistry/capacitor>. [3] Cowing, Keith. "Weightless Over Cleveland - Part 1: Floating Teachers." SpaceRef.com. 1 Oct. 2006. 20 Nov.
2008 <www.spaceref.com/news/viewnews.html?id=1159>. [4] Davis, Doug. "Gauss's Law." General Physics II. 2002. 20 Nov. 2008
<http://www.ux1.eiu.edu/~cfadd/1360/24gauss/gauss.html>. [5] "Electrostatic Charge and Bacterial Adhesion." Bite-Sized Tutorials. 7 Nov. 2008
<www.ncl.ac.uk/.../tutorials/electrostatic.htm>. [6] Goldberger, Sean. “Microstrip Patch Antenna Design using a Hybrid Transmission Line and Cavity Model,” Class
report, Dept. of Elec. and Comp. Engineering, Texas A&M Univ., College Station, Texas, 2008. [7] Long, S. A. “A Cognitive Compensation Mechanism for Deformable Antennas,” M.S. thesis, Dept. of Elec. and
Comp. Engineering, Texas A&M Univ., College Station, Texas, 2008. [8] Piazza, Daniele, Nicholas J. Kirsch, Antonio Forenza, Robert W. Heath, Jr., and Kapil R. Dandekar. “Design and
Evaluation of Reconfigurable Antenna Array for MIMO Systems." IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 56 (2008): 869-881.
[9] Sihvola, A. Electromagnetic Mixing Formulas and Applications. Washington, D.C.: Institution of Engineering and Technology (IET), 1999. 40-78.
[10] Zhang, S., G. H. Huff, J. Feng, and J. T. Bernhard. "A Pattern Reconfigurable Microstrip Parasitic Array." IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 52 (2004): 2773-2776.
Project Team
Back Center: Joel BarreraThird Row: Justin Marshall and Cameron Peters
Second Row: Rachel Anderson, Amy Bolon, and Stephen DavisFront Row: Sean Goldberger, David Umana, Jamie Edelen, and Frank Drummond