Feasibility and modeling of dynamic beamwidth control in partially reflective surface antennas

In this paper we propose the dynamic control of the beamwidth of partially reflective surface (PRS) antennas. Theoretical aspects are presented together with modeling issues. The potential and limitation of the concept are then evaluated. Finally, a detailed antenna design is proposed and validated by full-wave simulations

Design of Full-Metal Polarizing Screen Based on Circuit Modeling

International audienceA polarizing sheet based on a fully metallic structure is here reported for the first time. The polarizer consists of a doubly-periodic arrangement of squared-waveguide sections enclosed by two perforated screens. Though the waveguide sections are highly reactive (operating below cutoff), the perforations placed at both sides of the unit-cell allow for total transmission at a certain frequency band. Within this band, the unit-cell allows additionally to tune its anisotropy in order to transform the linear polarization of an impinging 45° -slant plane wave into circular. An equivalent circuit model of this structure is proposed that reproduces its full-wave scattering properties and explains its principle of operation. A design is performed operating around 20 GHz showing good performance. © 2018 IEEE

Circuit Modelling of Metallic Dual-Band Dual-Polarized FSS

International audienc

3D-printed Ka-band antenna based on stereolithography

International audienceThis paper presents a circularly-polarized dual-band antenna for Ka-band satellite communications which operates simultaneously in both civil and military downlink (17.7-21.2 GHz) and uplink (27.5-31 GHz) bands. The antenna is composed of a metallic ridged cavity that is perforated with a crossed-slot. This cavity is excited in sequential rotation through four feeding coaxial cables, thus producing circular polarization (CP). The required feed distribution is obtained by a dedicated beam-forming network (BFN) able to provide phases to generate right/left-handed CP in the downlink/uplink-bands, respectively. The prototype of the antenna cavity is 3D printed basing on stereolithography (SLA), while the BFN is realized in printed circuit technology. Good agreement is obtained between theoretical and measured results, thereby validating the antenna concept and confirming the strong potential of SLA to conceive compact RF components. © 2017 Euraap