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Abstract #0391

Mode Matching for the Modeling and Safety Assessment of Multiple-Channel Waveguide Transmission

Jan Paka1, David Otto Brunner2, Juerg Froehlich1, Klaas P. Pruessmann2

1Laboratory for Electromagnetic Fields and Microwave Electronics, ETH Zurich, Zurich, Switzerland; 2Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland

Travelling wave with multiple channels (TWM) is a new RF system. First experimental results in phantoms exist. For in-vivo imaging a careful safety assessment is necessary. EM-simulations of the TWM are difficult due to the large setup. In a previous work, the EM-domain was divided into subdomains and combined in a post-processing step, the FDTD method was used for EM-simulations, which has difficulties in modeling evanescent modes and the waveguide discontinuity. In this work this approach was extended. FEM was used for the simulation of all subdomains. The improved method yields more precise EM-simulations and a less conservative power limit.

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Keywords

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