%0 Journal Article
%A Divin, Yuri
%A Pandya, H. K. B.
%T Feasibility of ECE measurements using Hilbert-transform spectral analysis
%J Fusion science and technology
%V 65
%@ 0748-1896
%C La Grange Park, Ill.
%I American Nuclear Society
%M FZJ-2014-03630
%P 399-405 3
%D 2014
%X Electron cyclotron emission (ECE) from hot tokamak plasmas is recognized nowadays as a very informative diagnostic of main plasma parameters. Among several instruments developed to measure ECE, only a Martin-Puplett interferometer operates in a broadband frequency range of ECE from 70 to 1000 GHz. To derive the absolute radiation temperature of the plasma, a total measurement system, including front-end radiation collection, a transmission line, and the interferometer, is calibrated using a hot/cold calibration source. It takes a long time to calibrate the ECE system because of the high values of the noise equivalent power (NEP). A new technique, Hilbert-transform spectral analysis, is proposed for ITER plasma ECE spectral measurements. The operation principle, characteristics, and advantages of the corresponding Hilbert-transform spectrum analyzer (HTSA) based on a high-Tc Josephson detector are described. Because of the lower NEP values of the Josephson detector, this spectrum analyzer might demonstrate shorter calibration times than those for the Martin-Puplett interferometer. Because of a principal difference between Fourier and Hilbert transforms, the HTSA might have an additional advantage in retrieving harmonic ECE radiation from a continuous thermal background.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000336947200007
%U https://juser.fz-juelich.de/record/154254