Time-frequency analysis for microwave reflectometry data processing in the HL-2A tokamak.
Rev Sci Instrum
; 82(10): 103508, 2011 Oct.
Article
in En
| MEDLINE
| ID: mdl-22047295
ABSTRACT
The Choi-Williams distribution (CWD) technique is introduced as a time-frequency tool for processing data measured from the new developed homodyne and the fixed frequency reflectometry in the HL-2A tokamak. The comparison between spectrogram and CWD for the simulated signal is presented. It indicates that the CWD can greatly improve the representation of the time-frequency content of the multi-components signal. Its effectiveness is demonstrated through two applications in HL-2A, which are the extraction of beat frequencies from the frequency modulated-continuous wave reflectometry (FM-CW) and the characterizing of the fluctuations. The density profile inversed from the group delay of the FM-CW and the density fluctuations deduced from the fixed-frequency reflectometry would be more reliable and accurate by using the CWD technique.
Full text:
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Rev Sci Instrum
Year:
2011
Document type:
Article