"Features of Research on Extremely High Frequency Range Antenna Systems Using Compact Test Ranges"

"The specific aspects of experimental investigations of extremely high frequency range antennas using a spherical scanner based on a common kinematic scheme are considered. Analytical expressions are presented for solving wave diagnostics problems, enabling the calculation of the electromagnetic field distribution in the flat aperture of the antenna under test based on amplitude and phase measurements obtained in the far-field and near-field regions. The method for reconstructing the aperture field of the antenna under test using direct amplitude and phase measurements with a collimator is proposed. The wave diagnostics of antennas based on near-field measurements relies on determining the components of the vector amplitude spectra of homogeneous plane waves by the amplitudes of vector spherical waves. For both far-field measurements and collimator-based diagnostics, the fundamental principle involves calculating the components of the vector amplitude spectra of homogeneous plane waves from the amplitudes of spherical harmonics of the measured field components. Various configurations of measurement setups used for the experimental characterization of antennas and antenna systems are also presented."