Low Profile Dual Linearly Polarized 1-bit Transmitarray Exploiting Two Metallic Layers

Abstract

A novel azimuth-independent dual linearly polarized (LP) transmitarray (TA) based on a polarization rotator is presented. The exploitation of either right-handed circularly polarized (RHCP) or left-handed CP (LHCP) scattered field is at the basis of the proposed TA. The employed unit cell guarantees a low insertion loss as well as a crosspolar transmission phase difference of 0° or 180°. The TA unit cell response is insensitive to any angular rotation of the panel, or the primary feed, along $\varphi $ . The conceived dual-polarized 1-bit TA allows achieving up to 16.5 % of 3 dB gain bandwidth ( $BW_{3dB}$ ) with a maximum gain around 22 dBi and a peak aperture efficiency of 30.4 %. Unlike the previously reported dual-polarized TAs, this novel structure consists of a very thin dielectric layer, namely $0.08~\lambda _{0}$ at central frequency, comprising only two metallic layers making it a cost-effective solution as well as compliant with the increasingly strict profile requirements imposed by many of the future terrestrial and non-terrestrial wireless communication paradigms such as vehicular communications or SatCom systems. As a proof of concept, a prototype of the proposed dual-polarized 1-bit TA is manufactured and tested for assessing the benefits of this design approach.

Keywords

• Transmitarray
• frequency selective surfaces
• lens
• polarization