Synthesis and Characterization of a Focused-Beam Transmitarray Antenna at 300 GHz

This paper presents the synthesis, design and characterization of a centrosymmetric transmitarray antenna operating at 300 GHz. A broadside pencil beam with reduced sidelobe levels is obtained by fixing the illumination (i.e. feed and focal distance) and using a phase-only array synthesis procedure. The optimal aperture phase distribution is determined by means of an iterative convex optimization algorithm using semidefinite relaxation. Based on this distribution, a 400-element transmitarray comprising eight different unit cells is designed at 300 GHz, fabricated using low-cost printed circuit board technology and characterized. The measured results provide a first experimental validation of the synthesis approach.