Yu.V. Yukhanov - Ph. D. (Eng.), Head of Department of antenna, Southern Federal University. Е-mail: airpu@tgn.sfedu.ru
A.I. Semenikhin - Ph. D. (Eng.), Professor, Department of antenna, Southern Federal University. Е-mail: airpu@tgn.sfedu.ru
D.V. Semenikhina - Dr. Sc. (Eng.), Professor, Department of antenna, Southern Federal University. Е-mail: airpu@tgn.sfedu.ru

One of the known ways to improve the electromagnetic compatibility (EMC) antennas array (AA) is to set in front of them frequency-selective surfaces (FSS) as a shield. The shield has a low impact on the work of FSS in its own frequency band of and completely reflects electromagnetic waves outside this band. Creation of such a FSS-shield is, above all, complex electrodynamic problem. It consists of analyzing the reflection characteristics of a antennas array taking into account feed network, design of cells multilayer FSS, working off of the configuration of shield based on FSS when it scanning and at last, working off of all construction of system of FSS-shield taking into account EMC requirements and intrasystem electromagnetic interactions. Thus topology of FSS cells and shield form shall provide the small return loss and the given radiation characteristics of AA in operating band and in a sector of scan angles. Out of this band the FSS-shield shall provide the necessary EMC level in the given angular sector. In the paper the models of plane polarizable-independent FSS and waveguide array with FSS-shield of the semielliptical form are developed. The FSS model represents the infinite two-dimensional periodic array of densely packed mutually perpendicular H shaped slots in the plane ground on a dielectric substrate. The numerical analysis of characteristics covered AA in HFSS is made. It allowed to estimate influence of the semielliptical form of the shield on its frequency properties, on matching of AA, and also to estimate changes of radiation and scattering characteristics of all system of «FSS-shield». It is shown that the area of transparency of the shield of the semielliptical form displaces down on frequency approximately on 1 GHz in comparison with plane model of the infinite FSS. In the area of transparency the shield slightly changes the form of the main lobe of AA radiation pattern of the waveguide array. The null beamwidth increases in the H plane approximately for 9%; levels of the first two side lobes decrease on 1,5−3,5 dB, and far-out side lobe grow on 5−6 dB. Out of this area the shield in addition lowers backscattered field of AA (with a completely matching feed network) on 2−19 dB, but in bistatic scattering diagram of array there are the typical side lobes caused by diffraction on shield faces. The work performed at the Share Scientific Center «Applied Electrodynamics and antenna measurements», Southern Federal University, Russia.