Синтез и анализ диэлектрических бифокальных линз

Abstract

A technique is developed for the synthesis of dielectric bifocal lenses that convert two divergent cylindrical waves into convergent or flat ones. The technique is based on the well-known approach with setting the initial portion of the lens surface and sequentially finding other areas. The technique ensures the smoothness of the obtained solution. As an example, we synthesized three variants of bifocal lenses with different sets of parameters and an analysis of their aberrations. Analysis of aberrations showed that the lens, which forms flat fronts at the output, has a mean-square aberration of 1.25.10^-4, and for a lens with symmetrical focal curves it is 1.5.10^-3.Using the finite element method, a numerical study of the scanning characteristics of a planar bifocal lens antenna was carried out. A numerical experiment was performed to confirm the scanning properties of the synthesized lenses. A cylindrical dielectric bifocal antenna with a width of 160 mm and a height of 3.4 mm was located inside a planar metal waveguide of the same height and was excited by an H- sectorial horn with an input section of 7.2 × 3.4 mm and an output cross-section of 13 × 3.4 mm at a frequency of 37.5 GHz. The geometry of the focal curve was obtained by optimization by the criterion of maximum gain. In this case, the direction of the axis of the horn radiator was also optimized. Losses in metal and dielectric were not taken into account in the calculation. The antenna efficiency is more than 0.8 in the sector of angles ± 25 degrees, which considerably exceeds the sector of angles between the directions of formation of ideal flat fronts (± 13 degrees).

• диэлектрические линзы
• бифокальные линзы
• планарные линзы
• аберрации
• сканирование
• dielectric lenses
• Bifocal lenses
• Planar lenses
• aberrations
• scanning

For citation

References

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