Microwave Analysis with Monte Carlo Methods for ECH Transmission Lines

  • M. C. Kaufman
  • C. Lau
  • G. R. Hanson


A new code framework, MORAMC, is presented which model transmission line (TL) systems consisting of overmoded circular waveguide and other components including miter bends and transmission line gaps. The transmission line is modeled as a set of mode converters in series where each component is composed of one or more converters. The parametrization of each mode converter can account for the fabrication tolerances of physically realizable components. These tolerances as well as the precision to which these TL systems can be installed and aligned gives a practical limit to which the uncertainty of the microwave performance of the system can be calculated. Because of this, Monte Carlo methods are a natural fit and are employed to calculate the probability distribution that a given TL can deliver a required power and mode purity. Several examples are given to demonstrate the usefulness of MORAMC in optimizing TL systems.


ITER Transmission lines Electron cyclotron heating Monte Carlo 



The authors would like to thank Guiding Wang (UCLA) for providing experimental data for the transmission line losses of the ITER LFSR test stand and also Tim Bigelow (ORNL) for valuable discussion. This work was performed under the U.S. DOE contract no. DE-AC05-00OR22725.


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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Oak Ridge National LaboratoryOak RidgeUSA

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