Plasma and Fusion Research

Volume 3, S1045 (2008)

Regular Articles

Data Analysis Techniques for Microwave Imaging Reflectometry
Z. B. SHI, Y. NAGAYAMA1), S. YAMAGUCHI1), Y. HAMADA1) and Y. HIRANO2)
The Graduate University for Advanced Studies, Toki 509-5292, Japan
1)
National Institute for Fusion Science, Toki 509-5292, Japan
2)
National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan
(Received 11 December 2007 / Accepted 14 March 2008 / Published 1 August 2008)

Abstract

A data analysis technique for microwave imaging reflectometry (MIR) in the Large Helical Devices (LHD) and TPE-RX plasmas has been investigated. In LHD, the fast Fourier transform (FFT) is employed. The statistical properties of the fluctuation spectra on MIR signals are quantified by the time-frequency analysis by the ensemble average technique. Statistical analyses using cross-correlation and coherence spectra reveal the characteristics of MHD modes, such as wave numbers, mode numbers, and phase velocity. In TPE-RX, the wavelet analysis is more useful because the phenomena are transient in TPE-RX plasma.

Keywords

density fluctuation, microwave imaging reflectometry, ensemble average, wavelet, FFT.

DOI: 10.1585/pfr.3.S1045

Full Text

PDF format (1.0Mbytes) PDF Download

References

  • [1] S. Yamaguchi et al., Rev. Sci. Instrum. 77, 10E930 (2006).
  • [2] Y. Nagayama, S. Yamaguchi, Z.B. Shi et al, Proceedings of ITC/ISHW2007, P1-080.
  • [3] R. Sabot et al., Plasma Phys. Control. Fusion. 48, B421 (2006).
  • [4] H. Park et al., Rev. Sci. Instrum. 74, 4239 (2003).
  • [5] E. Mazzucato, Rev. Sci. Instrum. 69, 2201 (1998).
  • [6] E.B. Hooper, Plasma Physics 13, 1 (1971).
  • [7] Ch. P. Ritz et al., Rev. Sci. Instrum. 59, 1739 (1988).
  • [8] G.S. Xu et al., Physics of Plasmas. 13, 102509 (2006).
  • [9] A. Grinsted, J.C. Moore and S. Jevrejeva, Nonlinear Processes in Geophysics 11, 561 (2004).
  • [10] V.P. Budaev, I.M. Pankratov, S. Takamura et al., Nucl. Fusion 46, S175 (2006).
  • [11] S. Yamaguchi, Y. Nagayama, Z.B. Shi et al, Proceedings of ITC/ISHW2007, P1-082.
  • [12] T. Kass, H.S. Bosch, F. Hoenen et al., Nucl. Fusion 38, 807 (1998).
  • [13] Christopher Torrence and Gilbert P. Compo, Bulletin of the American Meteorological Society 79, 61 (1998).
  • [14] Y. Hinaro, Y. Maejima, T. Shimada et al., Nucl. Fusion 36, 721 (1996).
  • [15] P.R. Brunsell, Y. Maejima, Y. Yagi et al., Phys. Plasmas 1, 2297 (1994).

This paper may be cited as follows:

Z. B. SHI, Y. NAGAYAMA, S. YAMAGUCHI, Y. HAMADA and Y. HIRANO, Plasma Fusion Res. 3, S1045 (2008).