Numerical study of microwave imaging reflectometry for measurements of density fluctuations in a tandem mirror plasma

In this paper, numerical experiment is used to study the imaging properties of microwave imaging reflectometry for the case of tandem mirror device geometry. First of all, the alignment of the experimental setup is performed and then the imaging system is applied for density fluctuations measurements. Fluctuations employed in this study have a nonshifted Gaussian wavenumber spectrum with equal poloidal and radial widths. The size of the optics is shown to be a main parameter limiting the performance of the imaging system. Space-imaging and time-imaging modes are considered. In the latter case, for model conditions imaging and conventional (without optics) reflectometers demonstrate comparable performance in general. When root-mean-squared amplitude of the density fluctuations is large (σ n = 0.06 and 0.09) the imaging system shows a wider range of measurable parameters.

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