%0 Journal Article %T Circularly-Polarized Reconfigurable Transmitarray in Ka-Band with Beam Scanning and Polarization Switching Capabilities %+ Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI) %+ Institut d'Électronique et des Technologies du numéRique (IETR) %+ DGA Mission Recherche et Innovation Scientifique (DGA MRIS) %+ DGA Maîtrise de l'information (DGA.MI) %A Di Palma, L. %A Clemente, A. %A Dussopt, L. %A Sauleau, R. %A Potier, P. %A Pouliguen, P. %Z French Ministry of Defense (Direction Générale de l’Armement) %< avec comité de lecture %@ 0018-926X %J IEEE Transactions on Antennas and Propagation %I Institute of Electrical and Electronics Engineers %V 65 %N 2 %P 529--540 %8 2017 %D 2017 %R 10.1109/TAP.2016.2633067 %K Antenna lobes %K Bandwidth %K Circular polarization %K Frequency bands %K Lens antennas %K Microwave antennas %K Phase shift %K Polarization %K Substrate integrated waveguides %K Waveguides %K Beam-steering %K Discrete lens %K Planar lens %K Reconfigurable antenna %K Transmit arrays %K Horn antennas %Z Computer Science [cs]/Networking and Internet Architecture [cs.NI] %Z Engineering Sciences [physics]/ElectronicsJournal articles %X The design, realization, and experimental characterization of a 400-element electronically reconfigurable transmitarray operating in the Ka-band is presented. It is based on linearly polarized unit-cells with 180° phase-shifting capability. Several sequential rotation schemes have been compared numerically to generate a circularly polarized beam over a broad frequency band, and a random distribution has been selected to mitigate spurious cross-polarized side-lobes when scanning the main beam. The 2-D electronic beam-steering capabilities of ±60° have been verified experimentally. The prototype, illuminated by a horn antenna as a focal source, exhibits a broadside gain of 20.8 dBi at 29.0 GHz and a 3-dB bandwidth of 14.6% with radiation efficiency of 58%. The axial ratio remains below 2 dB within this bandwidth. Next, a planar substrate integrated waveguide focal source array was designed in order to reduce the focal distance by about 50% and thereby significantly improve the antenna compactness, and similar radiation performance is demonstrated numerically and experimentally. © 1963-2012 IEEE. %G English %L hal-01484525 %U https://univ-rennes.hal.science/hal-01484525 %~ CEA %~ UNIV-NANTES %~ UNIV-RENNES1 %~ CNRS %~ INSA-RENNES %~ IETR %~ IETR_SRC %~ STATS-UR1 %~ CENTRALESUPELEC %~ DRT %~ UR1-HAL %~ UR1-MATH-STIC %~ UR1-UFR-ISTIC %~ IETR-BEAMS %~ IETR-ADH %~ TEST-UNIV-RENNES %~ LETI %~ TEST-UR-CSS %~ UNIV-RENNES %~ INSA-GROUPE %~ CEA-GRE %~ TEST-HALCNRS %~ UR1-MATH-NUM %~ IETR-SUMIT %~ NANTES-UNIVERSITE %~ UNIV-NANTES-AV2022 %~ TEST3-HALCNRS