Studies of fluctuating plasma rotation by means of correlation and Doppler microwave reflectometry

A new approach to plasma rotation observation is microwave reflectometry. Poloidal correlation reflectometry uses cross-correlation analysis of microwaves reflected by 2 poloidally shifted parts of surface of toroidal fluctuating plasma. The reflected microwave signal is being modulated on amplitude and phase; this modulation contains information about time/space properties of perturbed reflecting surface. These perturbations are the result of plasma density perturbations in unstable plasmas. Poloidal plasma rotation will change temporal behavior of reflected signals. This change will be reflected in change of cross-correlation function of microwave detector signals. Doppler microwave reflectometry is another method of poloidal rotation velocity measurement. In this method the Doppler shift of microwaves reflected by fluctuating plasma is measured if probing antenna is tilted to the reflecting surface normal. This work is devoted to comparison of data coming from poloidal correlation and Doppler reflectometry for rotating plasma.