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A.O. Boryssenko1) & D.H. Schaubert2)

Antenna LaboratoryUniversity of Massachusetts

Amherst MA 01003 USA1)boryssen@ecs.umass.edu2)schaubert@ecs.umass.edu

UMass Method of Moment UWB Simulator

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Outline

Object-Oriented DesignProgramming in Matlab Macros ScriptsMulti- Component/Task/SolverTemplate LibrariesMatlab-Based Code with FORTRAN DLLs

Basic Concepts

Validation

Physical Phenomenology& Design of UWBLinks

Using Commercial EM SoftwarePrototyping, Practical Design & Tests

Optimal Driving WaveformsOptimal Termination ConditionsAntenna-Signal Co-DesignAntenna-Circuit Co-DesignMeeting to Different Link Merits Source Localization and Imaging with Arrays

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Preprocessor, Engines and Postprocessors

Preprocessor Engines Postprocessor

Geometry

Materials

Freq Domain

Time Domain

SPICE IntegrationArray Configurations

Antennas/Arrays

Tx/Rx Circuitry

Terminal & Radiation

… Supported in current FD version … Tested in other versions

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UMass MoM UWB Link Simulator :: Interface Basics

Four Key Element of Task Specification =Matlab Structural Variables

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Coding of Simulation Scene

Scene.DD=1.8;Scene.tol=1e-6;Scene.Unit='cm';Scene.Figure=1;%Scene.Component(1).Script='Geo_Antenna1';Scene.Component(1). Material=2;Scene.Component(1).MoveToPosition=[0 0 0]; Scene.Component(1).RotateToAngle=[0 0 0];Scene.Component(1).ZLoad=125;Scene.Component(1).ZLine=[125 4 1]; Two-antenna UWB link samples

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Flat Dipole Template

TEM Horn Template

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UWB Simulator Interface: Task Coding

%%% TASK #1%Task(1).Component(1).Port(1).Index=[1];Task(1).Component(1).Port(1).Amplitude=1;%%% TASK #2%Task(2).Component(1).Wave(1).Amplitude=1;Task(2).Component(1).Wave(1).DirectionOfArriving=[90 0];Task(2).Component(1).Wave(1).Polarization=[2];

Some key steps in simulation are GUI-supported

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%%% SOLVER%Solver(1).FreqBand=[0.05:0.75:4.0]'*1e9; % Hz;…

UWB Simulator Solver:: Specifications & Acceleration

Fast Pade Frequency Sweeping = Efficient Search for High-Q resonances

Uniform sampling over the freq. band

20 freq. sampling points are used

High-Q resonances are not accurately caught

Pade adaptive sampling over the freq. band

20 freq. sampling points are used

High-Q resonances are precisely evaluated

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UWB Simulator Interface: Post-Processor

%% Post #1 - ZINP%Post(1).ZINP.Task =1;Post(1).ZINP.Comp = 1;Post(1).ZINP.Port =1;Post(1).ZINP.Proc ='PadeApproxim_25';

Input Impedance of Tx Antenna

Smith Chart for Tx Antenna

Voltage at the load of Rx Antenna(Free-Space Propagation is Removed)

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Antenna-Circuit Co-Design for UW Link:: Optimal Antenna Termination to Tx/Rx Front-Ends

A.O. Boryssenko, D.H. Schaubert, Antenna Link Transfer Function Factorization Applied to Optimized Channel Design, To be submitted to IEEE Trans. on Antennas & Propagation

A.O. Boryssenko, D.H. Schaubert, Dispersive Properties of Terminal-Loaded Dipole Antennas in UWB Link, Submitted to IEEE 2006 Antennas & Propag. Symposium

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Antenna-Signal Co-Design for UW Link:: Optimal Driving Waveforms for Transmitter

Gaussian Pulse Optimal Signal “Matched” to FCC mask

Optimal Analog Pulse Optimal 3-bit Digitized Pulse

A.O. Boryssenko, D.H. Schaubert, Dispersive Properties of Terminal-Loaded Dipole Antennas in UWB Link, To be published in the Journal on VLSI Signal Processing, 2006

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∑=

+⋅

=RxN

kkjkkj

jFocused

cdtVtW

tU

1,,

,

)()(

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Known Signal Processing Techniques:Kirchhoff Migration … Fast FK Migration … Range Compression …Axial Compression …

Focused Image

Time-Domain Near-Field Beam Forming (Focusing)

Rx Array Collected Raw Signals

color keyed to receivers

Simulation of Antenna and Array Imaging :: Optimal Driving Waveforms for Transmitter

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Validation vs. Experiment in Two-Antenna Link

Phase of Received Voltage

Freq, GHz

Magnitude of Received Voltage

Time Response of Received Voltage

Time, ns

Freq, GHz

EM Coupling Between Two Probes over Finite Ground Plane