Assessment of the Operational Parameter Range for the Correlation Reflectometer on T-15md

The paper considers the operational frequency range and spatial accessibility of reflectometry for electron density fluctuation measurements in plasma core in the T-15MD tokamak. The primary limitation identified is the absorption of the probe beam at the fundamental and higher harmonics of the electron cyclotron resonance. The estimations were made for ordinary and extraordinary polarizations across a wide range of discharge scenarios. It was examined the configurations with different antenna location inside the vacuum vessel. The marginal fluctuation amplitude, under which the reflectometer works in linear regime, is assessed for the target density profile shape.