initial problems pieces

Effects of RF Pulses on Circuits and Systems – Pieces

UMCU UIC

1UIUCUH

Initial Problems Pieces

Develop Understanding of Coupling

Early Catalog of Expected Waveforms at Circuit Terminals

Incorporate into Topological Models


UMCU UIC

2UIUCUH

Short-Term ProblemsWires and Slots

• Obtain useful information quickly – 10 months

• Develop understanding of coupling mechanisms

• Assess influence of wires and slots on waveforms

• Catalog waveforms that can be expected at a pin of a digital system


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3UIUCUH

Wire Excited through Slot


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4UIUCUH

Wire through Hole


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5UIUCUH

Wires Coupled through Slot


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6UIUCUH

Slot Excited Wire between Plates


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7UIUCUH

Wire through Holes in Parallel Plates


UMCU UIC

8UIUCUH

Short-Term ProblemsCascaded Coaxial Cavities


• Develop understanding of coupling mechanisms involving cascaded cavities

• Assess influence of cascaded cavities on waveforms

• Catalog waveforms that can be expected at the terminus of a chain of cascaded cavities


UMCU UIC

9UIUCUH

Effects of Propagation Path on Transient Signal – Cascaded Cavities

Coax Terminationw/ Load

Casaded CoaxialCavities

Transient Signal Excitation

PlanarDiscontinuities


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10UIUCUH

Effects of Propagation Path on Transient Signal – Cascaded Cavities with Load

LZ

Load Im pedance

C asaded C oaxia lC avities

T ransient S ignal Excitation

P lanarD iscontinuities


UMCU UIC

11UIUCUH

Wire in Cascaded Cavities Loaded by Disk

C oax Term inationw/ Load



P lanarD iscontinuity R esistive D isk


UMCU UIC

12UIUCUH

Open Wire in Cascaded Cavities Loaded by Disk

R esistive D isk

C asaded Coaxia lC avities


P lanarD iscontinuity


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13UIUCUH

Coupling into Cascaded Cavities

LZ

PEC Screen

Load Im pedance

W ireSm all Entry H ole




Sm all H ole


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14UIUCUH


LZ

PEC Screen

Load Im pedance

Thin-W ire Antenna

Sm all Aperture





UMCU UIC

15UIUCUH


LZ

PEC Screen

Load Im pedance

Thin-W ire Antenna

Sm all Aperture




,qJ


UMCU UIC

16UIUCUH

Short-Term ProblemsFast Time-Domain Methods

Development

• Fast time-domain integral equation methods for inhomogeneous material regions

• Hybrid circuit theory -- TDIE analysis

• TDIE analysis for slowly varying (in time) fields

• Accurate TDIE for weak penetration through apertures


UMCU UIC

17UIUCUH

Proposed Effort (Year 1): Algorithms and Implementations

• Develop PWTD enhanced TDIE solvers with material capability (6 mo.)

• Interface PWTD enhanced TDIE solvers with SPICE-like circuit solver (12 mo.)

• Develop “low frequency” stable PWTD / TDIE solver (12 mo.)

– Hybridize loop/star/tree and time Galerkin schemes (Industry strength implementation)


UMCU UIC

18UIUCUH

Proposed Effort (Year 1): Demonstration of Capabilities

• Analyze coupling into a nonlinear circuit (amplifier) in a realistic enclosure (12 mo.)– Geometry: Slots, cavities, pins,

nonlinear circuitry.

– Demonstrates all capabilities of solver

– Validation: through comparison to FDTD solution.

slotcircuitry

cavityboards + pins


UMCU UIC

19UIUCUH

Short-Term ProblemsFast Frequency-Domain Methods

Development

• Fast frequency-domain integral equation methods for exterior-to-interior coupling problem – specialization of existing codes

• Fast frequency-domain integral equation methods for very low frequencies (for FFT)

• Fast hybrid methods -- specialization• Serve as checks of other more specialized analyses


UMCU UIC

20UIUCUH

EMI Threat to Aircraft SystemsAirborne Transmitter

Ground-based orship-board Transmitter

PEDSLightening

External Threat

• Coupling from other Aircraft Systems• Natural Environmental Effects (Lightening, Static Electricity)• Man Made Sources External to the aircraft (High Intensity Radiated Fields - HIRF)

Internal Threat

• Portable Electronic Devices (PEDS) carried by passengers

Picture from NASA-Langley


UMCU UIC

21UIUCUH

Penetration through Loaded Slots and Cracks

• Most typical coupling occurs through slots and cracks

• Closed form expressions will be developed for various 2D slots and 3D straight slots by analogy to wire scattering

• Develop an understanding of good shielding practices and relative levels of penetration among the various slots geometries

• Develop methods for equivalent circuit extraction


UMCU UIC

22UIUCUH

Coupling though Slots in Loaded Structure

• Develop general purpose frequency domain techniques for coupling into loaded geometries

• Validation of other techniques


UMCU UIC

23UIUCUH

Short-Term ProblemsApplication of EIGER


• Develop understanding of coupling mechanisms involving moderately complex structures

• Use as a quick check on more problem-specific analyses

• EIGER will also be used for longer-term complex problems


UMCU UIC

24UIUCUH

EIGEREIGER May Be Used for General-Purpose EM Calculations

and Code Validation

• EIGER is a general-purpose EM modeling code being developed jointly by

U. Houston Navy (SPAWAR) Lawrence Livermore Nat’l Lab Sandia Nat’l Labs

• Special purpose codes are likely to be needed to efficiently obtain the desired parameters in some cases.

• We anticipate using EIGER to obtain initial results,validate new codes, and perform general EM modeling.


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25UIUCUH

EIGEREIGER Takes A “Next Generation” Approach to Computational Electromagnetics

• Maintainability, extendibility, availability Current development efforts: U. Houston, U. Washington, Brigham Young, Virginia Tech

• A rich set of features allows treatment of complex problems using appropriate optimal combination of techniques

• Applicable to a wide variety of EM problems (antennas, RF, EMI, EMC, RCS, etc.)

Eiger can serve as “computational kernel” for special purpose applications, like FSSBuild, a periodic phased array and FSS

analysis interface

• High performance computing (HPC) capability incorporated into design

Object- oriented philosophy


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26UIUCUH

Generality allows one to select the right treatment for each part of a complex problem ...

Elements

Expansions Excitation

SolversOperatorsBoundary

Conditions

ElementsGreen’sFunc.

Expansions Excitation

Solversapertureaperturecouplingcoupling

edge edge treatmenttreatment

rotationalrotationalsymmetrysymmetry


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27UIUCUH

MURI-Related Example

Conducting Wire with 50 Loads, Terminated on Interior Walls of an Conducting Box with Two Apertures, Excited by a Voltage Source

+ -

0.4 m

0.6 m

0.36 m


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28UIUCUH

A Variety of Boundary Conditions are Required:

•Aperture

•Conducting surface

•Wire

•Terminating loads


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29UIUCUH

A Combination of Element, Excitation, and Current Types is Needed

Element types:

triangles

quadrilaterals

wires

Possible excitation types:

interior:

voltage source

exterior:

plane wave

V

Current types:

two-sided element, ,J M

single-sided element, J

wire element, J

initial problems pieces

Documents