A linear to circular polarization reconfigurable converter based on frequency selective surface

Abstract

In this article, a linear to circular polarization reconfigurable converter (PRC) working in transmission mode is proposed. The PRC's fundamental unit consists of a cascade of half-hexagon structure and its mirror replica printed on both sides of a single layer substrate. A PIN diode inserted in the central arm of the unit cell controls the PRC's behavior to a ϕ = 45° linearly polarized (LP) incident wave, transmitting an LP and circularly polarized (CP) in the ON and OFF state of the diode respectively. The proposed PRC is compact with an overall size of 0.046λ03 (λ0 is calculated with respect to 15.15 GHz) and exhibits a polarization conversion ratio greater than 0.9 in the frequency band 14.0–16.0 GHz. Polarization reconfigurable behavior of the converter is verified by placing 45°clockwise rotated 6 × 6 array of the proposed PRC's unit cell on top of an LP patch antenna. The transmitted radiation from the antenna with the PRC in ON and OFF state of the PIN diode is LP and CP (left or right). A prototype of the antenna with PRC is fabricated, and the results obtained from measurements are in agreement with simulated ones. © 2021 Wiley Periodicals LLC