Theoretical Assessment of Plasma Current Measurement in Tokamaks in Relation with the OTDR Detector Noise

Research output: Contribution to report/book/conference proceedingsIn-proceedings paperpeer-review


Institutes & Expert groups

  • BRNO - University of Technology
  • CEA Cadarache - Commissariat à l'Énergie Atomique
  • Masaryk University - Department of Geological Sciences, Faculty of Science
  • UMons - University of Mons-Hainaut

Documents & links


In this paper, we present a theoretical analysis of the plasma current measurement in tokamak-type fusion reactors using a Polarization Optical Time-Domain Reflectometer (POTDR) setup, where the general case of non-uniform distribution of a magnetic field along the sensing fibre is analyzed. A low birefringent fibre has been considered as the sensing fibre. The numerical simulations were based on the Jones formalism and take into account the OTDR detector noise reflecting the measurement error as a function of the plasma current. The measurement performance was evaluated for an ITER (International Thermonuclear Experimental Reactor)-relevant sensor configuration. Based on the simulation results we demonstrate that for plasma currents in the range of 0 to 1 MA, the signal-to-noise ratio (SNR) of 6 dB, achievable in modern POTDRs, complies with the ITER requirements. Subsequently, the SNR level of 4 dB satisfies the plasma current range of 1 to 20 MA.


Original languageEnglish
Title of host publication2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring)
PublisherIEEE - Institute of Electrical and Electronics Engineers
Number of pages5
ISBN (Print)978-1-7281-3403-1
Publication statusPublished - 2 Mar 2020
Event2019 - PhotonIcs & Electromagnetics Research Symposium: Spring (PIERS — SPRING) - University of Rome 'La Sapienza', Rome, Italy
Duration: 17 Jun 201920 Jun 2019


Conference2019 - PhotonIcs & Electromagnetics Research Symposium
Internet address


  • ITER, Tokomaks, OTDR detector noise

ID: 6784157