Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device

T. Notake, Hiroshi Idei, S. Kubo, T. Shimozuma, Y. Yoshimura, S. Kobayashi, Y. Mizuno, S. Ito, Y. Takita, K. Ohkubo, W. Kasparek, T. Watari, R. Kumazawa

    Research output: Contribution to journalArticle

    12 Citations (Scopus)

    Abstract

    The polarization state of a wave is an important factor in electron cyclotron resonance heating (ECRH) and current drive (ECCD), for it strongly affects the propagation and absorption of the wave in the plasma. A real-time monitor of the polarization of the EC beam has been developed for use in ECRH/ECCD experiments in large helical device (LHD). Two orthogonal components of the wave field are measured in one of the miter-bends by use of a specially designed coupler and a waveguide circuit with a 0°-90° phase switch to deduce the polarization parameters: the polarization angle α and the ellipticity β. Since fast-response pin diodes are used for the switches, the polarization is determined every 3 ms, facilitating real time acquisition of the polarization. This article reports on the design and the principle of this monitor as well as on the algorithm used to calculate α and β. This article also reports on the method of calibration, for the accuracy of this measurement depends on it. Finally, a comparison is made between polarization parameters measured by a monitor actually installed on one of the ECRH transmission lines on LHD and the value set by the polarizer in ECRH experiments.

    Original languageEnglish
    Article number023504
    JournalReview of Scientific Instruments
    Volume76
    Issue number2
    DOIs
    Publication statusPublished - Jan 25 2005

    Fingerprint

    Electron cyclotron resonance
    electron cyclotron resonance
    monitors
    Polarization
    Heating
    heating
    polarization
    Experiments
    switches
    Switches
    ellipticity
    polarizers
    couplers
    transmission lines
    Electric lines
    acquisition
    Diodes
    Waveguides
    diodes
    Calibration

    All Science Journal Classification (ASJC) codes

    • Instrumentation

    Cite this

    Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device. / Notake, T.; Idei, Hiroshi; Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Kobayashi, S.; Mizuno, Y.; Ito, S.; Takita, Y.; Ohkubo, K.; Kasparek, W.; Watari, T.; Kumazawa, R.

    In: Review of Scientific Instruments, Vol. 76, No. 2, 023504, 25.01.2005.

    Research output: Contribution to journalArticle

    Notake, T, Idei, H, Kubo, S, Shimozuma, T, Yoshimura, Y, Kobayashi, S, Mizuno, Y, Ito, S, Takita, Y, Ohkubo, K, Kasparek, W, Watari, T & Kumazawa, R 2005, 'Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device', Review of Scientific Instruments, vol. 76, no. 2, 023504. https://doi.org/10.1063/1.1848657
    Notake, T. ; Idei, Hiroshi ; Kubo, S. ; Shimozuma, T. ; Yoshimura, Y. ; Kobayashi, S. ; Mizuno, Y. ; Ito, S. ; Takita, Y. ; Ohkubo, K. ; Kasparek, W. ; Watari, T. ; Kumazawa, R. / Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device. In: Review of Scientific Instruments. 2005 ; Vol. 76, No. 2.
    @article{0664b567726342dd95fe7941a840fd14,
    title = "Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device",
    abstract = "The polarization state of a wave is an important factor in electron cyclotron resonance heating (ECRH) and current drive (ECCD), for it strongly affects the propagation and absorption of the wave in the plasma. A real-time monitor of the polarization of the EC beam has been developed for use in ECRH/ECCD experiments in large helical device (LHD). Two orthogonal components of the wave field are measured in one of the miter-bends by use of a specially designed coupler and a waveguide circuit with a 0°-90° phase switch to deduce the polarization parameters: the polarization angle α and the ellipticity β. Since fast-response pin diodes are used for the switches, the polarization is determined every 3 ms, facilitating real time acquisition of the polarization. This article reports on the design and the principle of this monitor as well as on the algorithm used to calculate α and β. This article also reports on the method of calibration, for the accuracy of this measurement depends on it. Finally, a comparison is made between polarization parameters measured by a monitor actually installed on one of the ECRH transmission lines on LHD and the value set by the polarizer in ECRH experiments.",
    author = "T. Notake and Hiroshi Idei and S. Kubo and T. Shimozuma and Y. Yoshimura and S. Kobayashi and Y. Mizuno and S. Ito and Y. Takita and K. Ohkubo and W. Kasparek and T. Watari and R. Kumazawa",
    year = "2005",
    month = "1",
    day = "25",
    doi = "10.1063/1.1848657",
    language = "English",
    volume = "76",
    journal = "Review of Scientific Instruments",
    issn = "0034-6748",
    publisher = "American Institute of Physics Publising LLC",
    number = "2",

    }

    TY - JOUR

    T1 - Real time polarization monitor developed for high power electron cyclotron resonance heating and current drive experiments in large helical device

    AU - Notake, T.

    AU - Idei, Hiroshi

    AU - Kubo, S.

    AU - Shimozuma, T.

    AU - Yoshimura, Y.

    AU - Kobayashi, S.

    AU - Mizuno, Y.

    AU - Ito, S.

    AU - Takita, Y.

    AU - Ohkubo, K.

    AU - Kasparek, W.

    AU - Watari, T.

    AU - Kumazawa, R.

    PY - 2005/1/25

    Y1 - 2005/1/25

    N2 - The polarization state of a wave is an important factor in electron cyclotron resonance heating (ECRH) and current drive (ECCD), for it strongly affects the propagation and absorption of the wave in the plasma. A real-time monitor of the polarization of the EC beam has been developed for use in ECRH/ECCD experiments in large helical device (LHD). Two orthogonal components of the wave field are measured in one of the miter-bends by use of a specially designed coupler and a waveguide circuit with a 0°-90° phase switch to deduce the polarization parameters: the polarization angle α and the ellipticity β. Since fast-response pin diodes are used for the switches, the polarization is determined every 3 ms, facilitating real time acquisition of the polarization. This article reports on the design and the principle of this monitor as well as on the algorithm used to calculate α and β. This article also reports on the method of calibration, for the accuracy of this measurement depends on it. Finally, a comparison is made between polarization parameters measured by a monitor actually installed on one of the ECRH transmission lines on LHD and the value set by the polarizer in ECRH experiments.

    AB - The polarization state of a wave is an important factor in electron cyclotron resonance heating (ECRH) and current drive (ECCD), for it strongly affects the propagation and absorption of the wave in the plasma. A real-time monitor of the polarization of the EC beam has been developed for use in ECRH/ECCD experiments in large helical device (LHD). Two orthogonal components of the wave field are measured in one of the miter-bends by use of a specially designed coupler and a waveguide circuit with a 0°-90° phase switch to deduce the polarization parameters: the polarization angle α and the ellipticity β. Since fast-response pin diodes are used for the switches, the polarization is determined every 3 ms, facilitating real time acquisition of the polarization. This article reports on the design and the principle of this monitor as well as on the algorithm used to calculate α and β. This article also reports on the method of calibration, for the accuracy of this measurement depends on it. Finally, a comparison is made between polarization parameters measured by a monitor actually installed on one of the ECRH transmission lines on LHD and the value set by the polarizer in ECRH experiments.

    UR - http://www.scopus.com/inward/record.url?scp=13744251123&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=13744251123&partnerID=8YFLogxK

    U2 - 10.1063/1.1848657

    DO - 10.1063/1.1848657

    M3 - Article

    AN - SCOPUS:13744251123

    VL - 76

    JO - Review of Scientific Instruments

    JF - Review of Scientific Instruments

    SN - 0034-6748

    IS - 2

    M1 - 023504

    ER -