Development of 180 GHz heterodyne radiometer for electron cyclotron emission measurements in JT-60U
- 1 January 1995
- journal article
- research article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 66 (1), 413-415
- https://doi.org/10.1063/1.1146364
Abstract
A 12‐channel heterodyne radiometer system has been developed to obtain electron temperature with high time and spatial resolution from the electron cyclotron emission (ECE) in JT‐60U. Resolutions of a single‐sideband‐type receiver are (1) Δt∼1 μs and (2) Δf=0.5 GHz. The second harmonic extraordinary mode of ECE is utilized for this system and the frequency band is 176–188 GHz. The noise level of the system is determined by unavoidable photon fluctuations, and the signal‐to‐noise ratio was measured to be about 50 with a video bandwidth of 100 kHz for a signal temperature above ∼200 eV. Details of the design, the obtained performance, and typical measurements are described.Keywords
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