3-D Printed Planar Dielectric Linear-to-Circular Polarization Conversion and Beam-Shaping Lenses Using Coding Polarizer

• Published in: IEEE transactions on antennas and propagation Vol. 68; no. 6; pp. 4332 - 4343
• Main Authors: Zhu, Jianfeng, Yang, Yang, McGloin, David, Rajasekharan Unnithan, Ranjith, Li, Shufang, Liao, Shaowei, Xue, Quan
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 3-D printing; beam shaping; Boundary conditions; Circular polarization; Coding; coding polarizer; Collimation; Conversion; Delays; Dielectrics; Encoding; lens; Lenses; millimeter-wave (mm-wave); pencil beam; Polarization; Polarizers; Three dimensional printing; Transmitting antennas
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2020.2972625

This article presents a new linear-to-circular polarization conversion coding unit, on which two new kinds of beam-shaping lenses are proposed. First, under periodic boundary conditions, a linear-to-circular polarization conversion coding unit is introduced, which introduces the necessary phase delay by adjusting its geometrical parameters. The phase delay ranges from 0° to 360° and is discretized into 3 bit coding units corresponding to specific delays. Second, by properly arranging the coding units, a high-gain circularly polarized (CP) lens is proposed. The lens achieves linear-to-circular polarization conversion and beam collimation in the transmission mode simultaneously with a planar configuration, which is different from counterparts that place a lens atop of a polarizer. Furthermore, the coding units are used to form Wollaston-prism-like and Rochon-prism-like planar CP beam-shaping lenses, which split the beams with different polarizations into right- and left-handed components. These beams can be controlled independently. Prototypes working at 30 GHz band are designed, fabricated, and measured to verify the idea.