Yu.Е. Kalinin - Dr.Sci. (Phys.-Math.), professor, head of the department of physics of solid state, Voronezh State Technical University
А.V. Ostankov - Dr.Sci. (Eng.), associate professor, professor, department of radio engineering, Voronezh State Technical University

Diffraction radiation antenna is one of the possible low-profile achievement versions of scanning antenna with SHF or EHF range. Its operating principle is based on a frequency-dependent effect of the mutual transformation of slow surface wave dielectric waveguide into the wave, radiating into free space, by a periodic grating. The antenna aperture is implemented as a combination of dielectric waveguide and diffraction grating, for example, "comb" type. Providing optimal amplitude distribution at the aperture is possible due to changes of the comb notch depth in lengthwise direction. The article describes the antenna calculation method. The calculation is based in part on a generalization of the known literary sources. In particular, the choice of parameters of a planar dielectric waveguides is based on the known solutions of the dispersion equation for the characteristic wave dielectric waveguide, shielded metal shield. For finding geometrics of the aperture is proposed to use proven author mathematical model. In assumption of comb aperture excitation by the slow wave of dielectric wave conductor the diffraction problem are leading to linear equations sets relatively notch mode by the Fourier method. The model takes to account edge effects and arbitrary law of comb-notch depth modification. It reveals depth profile that best meets the specified requirements to the technical antenna characteristics, using analysis of the antenna diagrams and characteristics of the secondary aperture. The key elements of the methodology are illustrated by example of the antenna of diffraction radiation with scanning in the asymmetric sector, relatively normal to the aperture.