In short, ECE radiometry of overdense plasmas was proved by considering, rather than ordinary (O) or extraordinary (X) mode emission perpendicular to the magnetic field, the black body emission of electron Bernstein (B) waves (EBWs) escaping the plasma after B-X-0 mode conversion along a special oblique sightline. The original features of such approach, compared to traditional ECE, are: 1. the antenna optimization with respect to transmittivity through the cutoff layer and with respect to the Doppler deformation of the spectrum, 2. the broadband phaseshifter, for modal purity measurements along the oblique sightline, 3. the mode-converted EBW ray tracing code in 3D hot plasma for profile recovery from spectra. Temperature profiles and diagnostic applications in a variety of conditions occurring at too high density for ECE (up to n_e = 3.5 · 10~(20)m~(-3)) and over too fast time scales for Thomson scattering (as fast as 1μs) have been presented. Moreover, for the first time the heat waves method has been extended beyond the ECE cutoff density combining EBW emission measurements at the first harmonic (f = 63 - 78GHz) with modulated EBW heating at the second harmonic (140GHz).
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