EM TECHNOLOGY

CEM

Research Objectives

The objectives of IT'IS simulation and numerical analysis research are targeted at remaining the pacemaker in computational electromagnetics (CEM) in complex environments by:

performing basic research in computational electromagnetics (FDTD (finite-difference time-domain) and in combination with FE (finite elements), MoM (method of moments))
focusing specifically on exploiting high-performance computing (HPC) technologies (GPU (graphics processing unit), Cell, CUDA (compute unified device architecture), OpenCL, etc.)
developing advanced and effective method extensions and features in cooperation with leading providers of EM simulation platforms
maintaining an advanced HPC infrastructure
benchmarking our methods and tools through validation against “real-world” scientific and industrial applications

IT'IS simulation and numerical analysis research strives for an ongoing active collaboration with leading partners within universities and industry.

Past Achievements

The IT'IS simulation and numerical analysis group has contributed novel techniques to the international CEM community for more than 10 years and pioneered numerous pacemaking achievements, a selection of which is provided as follows:

Methods

A. Christ, J. Fröhlich, and N. Kuster, “Correction of numerical phase velocity errors in nonuniform FDTD meshes”, IEICE Transactions on Communications, Volume E85-B, Issue 12, pp. 2904–2915, December 2002.
N. Chavannes and N. Kuster, “A novel 3-D CPFDTD scheme for modeling grid non-conformally aligned transmitter structures”, IEEE Transactions on Antennas and Propagation, vol. 52, pp. 1324–1334, May 2004.
N. Chavannes, “Nonuniform grids, nonorthogonal grids, unstructured grids, and subgrids”, in Computational Electrodynamics: The Finite-Difference Time-Domain Method, Allen Taflove, Ed., chapter 11.8. Artech House, Norwood, MA 02062, 3rd edition, June, 2005.
S. Benkler, N. Chavannes and N. Kuster, “A new 3-D conformal PEC FDTD scheme with user-defined geometric precision and derived stability criterion”, IEEE Transactions on Antennas and Propagation, Volume 54, Issue 6, pp. 1843-1849, June 2006.
A. Christ, S. Benkler, J. Fröhlich, and N. Kuster, “Analysis of the accuracy of the numerical reflection coefficient of the finite-difference time-domain method at planar material interfaces”, IEEE Transactions on Electromagnetic Compatibility, Volume 48, Issue 2, pp. 264–272, May 2006.
S. Schild, N. Chavannes, and N. Kuster, “A robust method to accurately treat arbitrarily curved 3-D thin conductive sheets in FDTD”, IEEE Transactions on Antennas and Propagation, vol. 55, pp. 3587–3594, December 2007.
S. Benkler, N. Chavannes and N. Kuster, “Mastering Conformal Meshing for Complex CAD-Based C-FDTD Simulations”, in IEEE Antennas and Propagation Magazine, Volume 50, Issue 2, pp. 45–57, April 2008.
S. Schild, “Advances in Material Modeling in EM-FDTD”, PhD Thesis, Swiss Federal Insititute of Technology, Thesis No. 17969, Zurich, 2008.

Applications

N. Chavannes, R. Tay, N. Nikoloski, and N. Kuster, “Suitability of FDTD based TCAD tools for RF design of mobile phones”, IEEE Antennas and Propagation Magazine, vol. 45, pp. 52–66, December 2003.
P. Futter, N. Chavannes, N. Nikoloski, N. Kuster, J. Keshvari, and A. Toropainen, “TCAD of mobile phones: Heading for a generic modeling approach”, in 6th International Congress of the European Bioelectromagnetics Association (EBEA), Budapest, Hungaria, Nov. 2003, p. 100.
A. Christ, N. Chavannes, N. Nikoloski, H.-U. Gerber, K. Pokovic, and N. Kuster, “A numerical and experimental comparison of human head phantoms for compliance testing of mobile telephone equipment”, Bioelectromagnetics, vol. 26, no. 2, pp. 125–137, Feb. 2005.
A. Christ, A. Klingenböck, T. Samaras, C. Goiceanu and N. Kuster, “The dependence of electromagnetic far-field absorption on body tissue composition in the frequency range from 300 MHz to 6 GHz”, IEEE Transactions in Microwave Theory and Techniques, Volume 54, Issue 5, pp. 2188–2195, May 2006.
P. Futter, N. Chavannes, R. Tay, M. Meili, A. Klingenböck, K. Pokovic and N. Kuster, “Reliable prediction of mobile phone performance for realistic in-use conditions using the FDTD method”, in Antennas and Propagation Magazine, IEEE, Volume 50, Issue 1, pp. 87–96, February 2008.
C-H. Li, E. Ofli, N. Chavannes, and N. Kuster, “Effects of Hand Phantom on Mobile Phone Antenna Performance”, in IEEE Transactions on Antenna and Propagation, Volume 57, Issue 9, pp. 2763–2770, September 2009.

Past and Current Selected Research Projects

CTI SEMCAD++ (2000-2003)

The main research topics of this project were focusing on enhanced modeling capabilities of FDTD, and improved accuracy of the scheme to create novel and robust techniques, which overcome parts of the FDTD techniques’ limitations. Furthermore, SEMCAD was continuously improved with advanced modeling and interfacing support for the user, as well as uncertainty prediction.

CTI TRINITY (2003-2006)

This project aimed to satisfy the scientific challenges and demands of the IT and medical industries for CEM simulation tools for analyzing and optimizing the performance of next generation wireless applications. The scientific challenges of TRINTY were the research in new and more effective solvers based on ADI-FDTD, the development of novel material models for optical device simulations, and the development of enhanced subcell models.

CTI LOVESim (2007-2009)

The objective of this project was to develop a versatile and robust electromagnetic simulation tool in the low frequency or static range with extended capabilities, including highly inhomogeneous full body anatomical human models. The final code is being utilized to show compliance with electromagnetic safety limits at work places, to improve medical therapeutic and diagnostic applications, and to improve the reliability for a large variety of industrial products.

CTI POSEIDON (2009-2011)

In this project, the algorithms and solvers for the next generation of waveguide and high-power devices will be developed, combined with novel HPC techniques, and integrated into a high-level simulation platform. The simulation platform will allow the analysis, synthesis and optimization of micro- and millimeter-wave devices built on cutting edge technologies from the aerospace, wireless communication, and healthcare industries. POSEIDON remedies the existing lack of mature integrated simulation platforms in industry and academia that are capable of interacting with other simulation tools within an all-encompassing multiphysics strategy.

Research Challenges

To remain the pacemaker in computational electromagnetics and in numerics research in general, and to expand its activities in related fields, the IT'IS Foundation focuses on a range of R&D and implementation projects. A selection encompasses the following topics:

keeping up with providing the fastest solvers in the community; developing novel solvers optimized for HPC environments, e.g., using OpenCL/MPI for distributed-memory cluster multi-GPU systems.
developing novel algorithms and methods to effectively address the next generation of waveguide and high-power devices – including optimization techniques, HPC, cloud computing and touching high-power phenomena (corona/multipactor effects).
addressing the latest needs of the optics community by developing novel material models, additional non-linear phenomena, advanced signals and sources, etc.
developing and implementing specific CEM models and materials on HPC hardware, e.g., SIBC (surface interface boundary condition), conformal surfaces, etc.
extending the solver suite to incorporate other methods, i.e., operating in frequency-domain (FD) or on unstructured grids.
performing physics- (mechanics-) based deformation of models for posing and organ shape modification; developing more sophisticated high-resolution anatomical models with appropriate meshes.
generating additional models (elderly person, small children, animals, etc.).
developing special models and schemes addressing ESD (electrostatic discharge) simulation and analysis of EMI/EMC phenomena; adapting specific postprocessing routines to reflect its evaluation needs.
assessing, developing and implementing routines to handle and process massively large datasets – on the pre- and postprocessing side, including its distribution over the network (e.g., on cloud computing systems).
developing novel and fast routines for evaluation of averaged SAR (specific absorption rate).
extending collaborations and projects between IT'IS and renowned leading institutions and research groups around the world.

Mobile phone - head - hand:
The algorithms developed within the framework of IT'IS allow the EM simulation and visualization of highly complex configurations (many more than 1e3 CAD parts, many more than 1e8 unknowns) within just a few minutes (GPU accelerated).

Ring coupler:
The development of novel material models (real metal, dispersive, double-negative, non-linear) allows the straightforward simulation of complex phenomena and structures in the optics area.

Posable anatomical phantoms:
The Poser Engine, implemented in the framework of CTI LOVESim, enables quick assignment of any physiological posture to the entire range of IT'IS's anatomical CAD models. Poser guarantees the connectivity of tissues and volume preservation.

Microwave applications:
Within the framework of the currently conducted CTI project POSEIDON, IT'IS – together with its partners – is developing algorithms and procedures to allow more effective simulation and optimization of microwave structures and space related phenomena, such as the multipactor effect.

Multi-GPU board:
The performance of the recent graphics processing unit (GPU) technology (e.g., by NVIDIA and AMD/ATI) initiated the development of optimized CEM related code. Speedups in computation of several orders of magnitude are thus possible.

Shielding on printed circuit board (PCB):
The variety of novel algorithms developed as well as GPU acceleration allow the simulation of very detailed structures (sub-micron range) within affordable time. Topical applications include, e.g., shielding and general EMI effects on PCBs.

Operator on power line:
CTI LOVESim also enabled us to develop a finite-element method (FEM) based solver operating on rectilinear grids – targeted for low frequencies. The suite encompasses static and quasi-static solvers for the E- and H-fields.

Chip - signal analysis in time-domain:
The developed and implemented co-simulation engine allows the simulation of coupled EM and circuit processes in time-domain (TD) using SPICE. The TD approach enables the identification of transient phenomena and noise, which gets lost in common FD schemes.

Conformal modeling:
Straightforward Yee-FDTD leads to a "staircased" approximation of non-conformally aligned structures. The novel conformal (C-FDTD) approach we developed overcomes this limitation and allows faster or more accurate simulations.

Optimization of MTE:
Genetic Algorithm (GA) optimization of a CAD based mobile phone antenna in in-use position. The developed GA allows complex multi-parameter multi-goal optimizations, distributed on a network (cloud computing).

Combination of large and detailed structures:
The Generalized Huygens Box approach we developed allows different domains and methods to be effectively interconnected via a generalized Total-Field Scattered-Field (TFSF) plane wave excitation and the Block Iterative Technique, which solves weakly coupled problems successfully.

Research Objectives

Past Achievements

Methods

Applications

Past and Current Selected Research Projects

CTI SEMCAD++ (2000-2003)

CTI TRINITY (2003-2006)

CTI LOVESim (2007-2009)

CTI POSEIDON (2009-2011)

Research Challenges

Mobile phone - head - hand:The algorithms developed within the framework of IT'IS allow the EM simulation and visualization of highly complex configurations (many more than 1e3 CAD parts, many more than 1e8 unknowns) within just a few minutes (GPU accelerated).

Ring coupler:The development of novel material models (real metal, dispersive, double-negative, non-linear) allows the straightforward simulation of complex phenomena and structures in the optics area.

Posable anatomical phantoms:The Poser Engine, implemented in the framework of CTI LOVESim, enables quick assignment of any physiological posture to the entire range of IT'IS's anatomical CAD models. Poser guarantees the connectivity of tissues and volume preservation.

Multi-GPU board:The performance of the recent graphics processing unit (GPU) technology (e.g., by NVIDIA and AMD/ATI) initiated the development of optimized CEM related code. Speedups in computation of several orders of magnitude are thus possible.

Shielding on printed circuit board (PCB): The variety of novel algorithms developed as well as GPU acceleration allow the simulation of very detailed structures (sub-micron range) within affordable time. Topical applications include, e.g., shielding and general EMI effects on PCBs.

Operator on power line:CTI LOVESim also enabled us to develop a finite-element method (FEM) based solver operating on rectilinear grids – targeted for low frequencies. The suite encompasses static and quasi-static solvers for the E- and H-fields.

Chip - signal analysis in time-domain:The developed and implemented co-simulation engine allows the simulation of coupled EM and circuit processes in time-domain (TD) using SPICE. The TD approach enables the identification of transient phenomena and noise, which gets lost in common FD schemes.

Conformal modeling:Straightforward Yee-FDTD leads to a "staircased" approximation of non-conformally aligned structures. The novel conformal (C-FDTD) approach we developed overcomes this limitation and allows faster or more accurate simulations.

Optimization of MTE:Genetic Algorithm (GA) optimization of a CAD based mobile phone antenna in in-use position. The developed GA allows complex multi-parameter multi-goal optimizations, distributed on a network (cloud computing).