Design of Electromagnetic Metasurfaces for Directional Scattering in High Temperature Environment

In this paper, a typical three-layer structure - metal/dielectric/patterned metal element surface is presented. The unit cell of the metasurface is composed of rectangular patch element. Based on the generalized laws of reflection, by discontinuous phase difference, abnormal reflection is realized. The thickness of the dielectric substrate is 3 mm. By calculating and optimizing the length and width of the patch element, 12 basis elements are selected, and the phase difference is 30 degrees. The reflection amplitude of every element is greater than 0.9. Based on the patch elements, a supercell that is arranged in a 12 by 12 array is realized. The size of the metasurface is 180 mm × 180 mm. Under normal incidence, at 5 GHz, the main lobe is deflected about negative 41 degrees away from the normal direction as was expected. Thereby, the main lobe of the mirror is effectively suppressed. The directional scattering properties of the proposed matesurface when environment temperature is high are also considered. The environmental temperature affects the electromagnetic parameters of the pattern layer and the dielectric layer. The simulation is performed and the results show an acceptable agreement with the numerical calculation. Metasurfaces realized with rectangular patch have the advantages in design and manufacture.