Ultrafast broadband frequency modulation of a continuous wave reflectometry system to measure

Silva, A.; Manso, M.E.; Cupido, L.; Albrecht, M.; Serra, F.; Varela, P.; Santos, J.; Vergamota, S.; Eusebio, F.; Fernandes, J.; Grossmann, T.; Kallenbach, A.; Kurzan, B.; Loureiro, C.; Meneses, L.; Nunes, I.; Silva, F.; Suttrop, W.
December 1996
Review of Scientific Instruments;Dec1996, Vol. 67 Issue 12, p4138
Academic Journal
Discusses the development of a reflectometry system for ASDEX Upgrade to measure the plasma profile from the scrape-off layer until the bulk plasma. Ultrafast broadband frequency modulation of a continuous wave; Use of solid state stable hyper abrupt tuned oscillators; Special design of the transmission line; Elimination of spurious reflections.


Related Articles

  • Theoretical aspects of the use of pulsed reflectometry in a spheromak plasma Cohen, Bruce I.; Hooper, E. Bickford; Bickford Hooper, E.; Spang, M. C.; Sprang, M.C.; Domier, C. W.; Domier, C.W. // Review of Scientific Instruments;Feb1999, Vol. 70 Issue 2, p1407 

    Addresses the theoretical issues associated with the use of reflectometry in the Sustained Spheromak Physics Experiment plasma experiment at the Lawrence Livermore National Laboratory in California. Extension of a reflectometry simulation model to accommodate O- and X-mode mixed polarization...

  • Analytic results in the theory of reflectometry in multidimensional plasma (abstract). Afeyan, Bedros B.; Cohen, Bruce I.; Crotinger, James A.; Williams, Edward A. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p402 

    Describes the results of measuring the multidimensional plasma of a model reflectometry. Range of reflectometry signals from controlled plasmas; Extent of discrepancies.

  • Geometrical optics interpretation of the phase runaway in microwave reflectometry. Branas, B.; Hirsch, M.; Sanchez, J.; Zhuravlev, V. // Review of Scientific Instruments;Jan1999, Vol. 70 Issue 1, p1025 

    Presents experimental results on plasmas obtained with a heterodyne/amplitude modulated reflectometer at the W7-AS shear modulator stellarator. Existence of a phase runaway and reproduction of the typical behavior of the measured phase and amplitude signals; Impossibility of deducing the plasma...

  • Reflectometry as a fluctuation diagnostic: A one-dimensional simulation. Chou, A. E.; Luhmann, N. C.; Peebles, W. A.; Rhodes, T. L. // Review of Scientific Instruments;Oct92, Vol. 63 Issue 10, p4669 

    Reflectometry is currently employed to characterize turbulence in fusion plasmas worldwide and is expected to be a major diagnostic on the next generation of machines (e.g., ITER). Until recently, little was known about the response of a reflectometer to fluctuations (degree of localization of...

  • Fundamental investigation of reflectometry as a density fluctuation diagnostic (invited). Rhodes, T. L.; Baang, S.; Chou, A. E.; Domier, C. W.; Luhmann, N. C.; Peebles, W. A. // Review of Scientific Instruments;Oct92, Vol. 63 Issue 10, p4599 

    Reflectometry is currently used to monitor density fluctuations and turbulent correlation lengths in fusion plasmas. Various models have been used to interpret the experimental data and to determine the regimes of validity of the reflectometer fluctuation measurements. Heretofore, these models...

  • Effects of turbulent fluctuations on density measurements with microwave reflectometry in... Mazzucato, E.; Nazikian, R. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p855 

    Examines the impact of short-scale turbulence of tokamak plasmas on the measurement of plasma density with microwave reflectometry. Large amplitude and phase modulations attributed to density fluctuations.

  • Reflectometer measurements of density fluctuations in tokamak plasmas (invited). Nazikian, R.; Mazzucato, E. // Review of Scientific Instruments;Jan1995, Vol. 66 Issue 1, p392 

    Observes anomalous features in reflectometer measurements of turbulent fluctuations in tokamak plasmas. Loss of coherent reflection; Large amplitude fluctuations; Large angular divergence of reflected waves.

  • One- and two-dimensional simulations or ultra-snort-pulse reflectometry (abstract) Cohen, Bruce I.; Kaiser, Thomas B.; Garrison, John C. // Review of Scientific Instruments;Jan1997, Vol. 68 Issue 1, p477 

    Reports on a study which examined ultra-short-pulse reflectometry by means of the numerical integration of one- and two-dimensional full-wave equations for ordinary and extraordinary modes propagating in plasma. Identification of Bragg resonance effects; Correlation reflectometry measurements.

  • Radial wave number spectrum of density fluctuations deduced from reflectometry phase signals. Heuraux, S.; Hacquin, S.; da Silva, F.; Clairet, F.; Sabot, R.; Leclert, G. // Review of Scientific Instruments;Mar2003, Vol. 74 Issue 3, p1501 

    A method to extract the radial wave-number spectrum of the density fluctuations from the reflectometry phase signal is proposed and the main points to interpret it are described. The method buildup is based on reflectometry studies devoted to phase or amplitude variations induced by coherent...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics