Dual Lens Focusing System with In-Lens Polarizer for Automotive Radar Sensors


Progress In Electromagnetics Research C, vol.124, pp.155-165, 2022 (Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 124
  • Publication Date: 2022
  • Doi Number: 10.2528/pierc22062004
  • Journal Name: Progress In Electromagnetics Research C
  • Journal Indexes: Scopus, Applied Science & Technology Source, Compendex, INSPEC
  • Page Numbers: pp.155-165
  • Yıldız Technical University Affiliated: Yes


© 2022, Electromagnetics Academy. All rights reserved.—This article presents a circularly polarized (CP) dual lens (DL) antenna with high gain and wide axial ratio (AR) bandwidth for automotive radar applications. Proposed antenna system provides low AR and scan loss over a wide angular range. It consists of a linearly polarized (LP), wide band, aperture coupled planar feed antenna, an extended hemispherical lens and a planoconvex lens with thin parallel plates and air slabs. In-lens polarizer mounted to the flat surface of the planoconvex lens converts LP wave to CP state. Fundamental design rules to obtain CP is defined. A CP DL design in low dielectric permittivity material (εr = 3) is introduced. It achieves simulated efficiency that varies between 75 and 82% within the 77–81 GHz automotive radar band. AR is below 2.2 dB for all scan angles up to 25◦. Realized gain at boresight radiation is 25.6 dBic at the center frequency. 0.85 dB scan loss is observed at ±30◦ scan angle. A frequency-scaled prototype has been fabricated by additive manufacturing process with fused deposition modeling, and the concept is proved by the experimental results in 22–28 GHz band.