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Andre Rennings, BA 345, andre.rennings@uni-due.de

Computerorientierte Feldtheorie 1Computational Electromagnetics 1

Electromagnetic Simulation Software 1

Introductory Lecture23.10.2009

PoiSolve

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Outline

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Why computer-aided methods are used?

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Why computer-aided methods are needed?

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Fundamentals of simulations

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� As analytical solutions are difficult (or impossibl e), there exist many

computational methods that are based on approximati ons of Maxwell’s

equations and/or boundary conditions and/or materia l properties.

� ”The power of analytical models over full-wave comp utational simulations is

the significantly lower calculating time. With anal ytical models and modern

mathematical software (like MATLAB or MAPLE), the s olving time is decreased

into seconds. The analytical result is always more or less an approximation,

whereas the EM simulation is as exact as the user’s know-how with the

simulator enables. However in practical design, the value of the saved

calculation time is multiple times worth of the dec reased accuracy when the

limits of the model are acknowledged...”

� What do you think?

Fundamentals of simulations

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Electromagnetic simulators

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Approaches to field solutions

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Fundamentals of simulations

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Fundamentals of simulations

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Fundamentals of simulations

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Important simulation parameters

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Checklist for accuracy

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Summary: Importance & place of numerical methods

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Various numerical methods

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Classification of numerical methods

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Frequency domain vs. time domain methods

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Advantages of FD modelling

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Advantages of TD modelling

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Finite Element Method, FEM

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Some features of FEM

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Finite Difference Time Domain, FDTD

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Some features of FDTD

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Method of Moments, MoM

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Some features of MoM

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Expansion functions

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MoM, FEM, FDTD – Comparison I

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MoM, FEM, FDTD – Comparison II

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Conclusions

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