RT Journal Article ID 2a5668a761cb500c A1 Nickolaev, S. V. A1 Pozhar, V. V. A1 Dzyubenko, M. I. T1 INFLUENCE OF THE EXCITATION FREQUENCY ON THE LASING CHARACTERISTICS OF THE DYE LASERS WITH COHERENT PUMPING JF Telecommunications and Radio Engineering JO TRE YR 2014 FD 2014-12-12 VO 73 IS 20 SP 1831 OP 1842 K1 interferometers K1 irredundant configurations K1 planar difference sets K1 square arrays K1 hexagonal arrays AB High-resolution images in radio and optical astronomy are obtained with the use of interferometers which elements form an irredundant configuration. With a given number of elements, interferometers of the kind are capable of measuring the maximum number of spatial frequencies and also make it possible to use methods which allow eliminating phase fluctuations produced by the medium inhomogeneity. The process of developing a mathematical model of an interferometer of the kind with a 2D aperture requires a large amount of computations which sharply increases with the number of elements when it is necessary to enlarge the aperture size. The conventional statistical methods prove to be insufficiently efficient in this case. The present paper suggests a regular technique for development of the mathematical models of 2D apertures representing integral arrays with an irredundant configuration of the elements. The method is based on the use of the special combinatorial structures which are planar difference sets. The properties of these sets are briefly described and the practice of their use for solving the assigned problems is described. In the paper, the irredundant configurations with the maximized number of elements in the square and hexagonal arrays, as well as those providing the complete coverage of the central part of the spatial frequency range are constructed. The maximum possible number of the elements of the irredundant configuration is estimated for the arrays of these kinds. The suggested method makes it possible to construct irredundant configurations with the maximized number of elements in the 2D large-aperture arrays. The technique can be used for solving optimization problems in the course of designing interferometer systems intended for astronomical research. The approach is more efficient as compared with the statistical ones with respect to the amount of calculations and the necessary computation time. PB Begell House LK https://www.dl.begellhouse.com/journals/0632a9d54950b268,7c46329e09f5b7af,2a5668a761cb500c.html