Millimeter-wave reflectometers for performing density fluctuations have traditionally used either
tunable fixed frequency (heterodyne and homodyne) systems or multichannel fixed frequency
arrangements. Only recently novel systems were brought into operation with the ability to hop from
one frequency to another over a large bandwidth, during each plasma discharge, while retaining the
quality of fixed frequency phase locked sources. The new broadband fast hopping millimeter-wave
reflectometer incorporates frequency synthesizers for both plasma signal and local oscillators, and
the receivers are heterodyne producing full phase/amplitude outputs. Two identical systems were
recently installed in (ASDEX upgrade tokamak - IPP-MPG Germany) covering the Q band
(33–50 GHz) and the V band (50–75 GHz). In the present article the system is described and the
particular implementation on ASDEX, using monostatic antenna system, is presented showing the
possibility of correlation studies in fully optimized antenna scenarios. With both Q and V channels
in operation it was possible to devise several operation schemes that are described here and a result
showing the radial localization of magnetohydrodynamic activity is also presented.
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