Programmable multifunctional metasurface for polarization, phase, and amplitude manipulation.

Metasurfaces have shown extraordinary capability in individually manipulating various electromagnetic (EM) properties, including polarization, phase, and amplitude. However, it is still a challenge to manipulate these EM properties in one metasurface simultaneously. In this paper, a programmable multifunctional metasurface (PMFMS) is demonstrated with polarization, phase, and amplitude manipulation abilities. By controlling tunable coding states and changing the direction of incident waves, the PMFMS can operate as a transmission cross-polarization converter, spatial wave manipulator, and low-RCS radome. Besides, the PMFMS possesses an ultra-wideband property, which can operate from 6.5 to 10.2 GHz with 44.3% relative bandwidth. More importantly, multiple functionalities can also be achieved in reflection operating mode by reassembling the PMFMS. As a proof of concept, the PMFMS is fabricated and experimentally verified. Measured results are in good agreement with simulated results. Benefiting from multifunctional EM manipulations in an ultra-wideband, such a design can be applied in wireless communication systems, radar detection, and EM stealth platform.

Electronically reconfigurable transmitarray for fully independent beam manipulation in two divided frequency bands.

Electronically reconfigurable transmitarray (ERTA) combines the advantages of optic theory and coding metasurface mechanism with the characteristic of low-loss spatial feed and real-time beam manipulation. Designing a dual-band ERTA is challenging due to multiple factors, including large mutual coupling generated by dual-band operation and separate phase control in each band. In this paper, a dual-band ERTA is demonstrated with the capability of fully independent beam manipulation in two divided bands. This dual-band ERTA is constructed by two kinds of orthogonally polarized reconfigurable elements which share the aperture in an interleaved way. The low coupling is achieved by utilizing polarization isolation and a backed cavity connected to the ground. To separately control the 1-bit phase in each band, a hierarchical bias method is elaborately presented. As proof of concept, a dual-band ERTA prototype composed of 15 × 15 upper-band elements and 16 × 16 lower-band elements is designed, fabricated, and measured. Experimental results verify that fully independent beam manipulation with orthogonal polarization is implemented in 8.2-8.8 GHz and 11.1-11.4 GHz. The proposed dual-band ERTA may be a suitable candidate for space-based synthetic aperture radar imaging.

A Novel Circularly Polarized Folded Transmitarray Antenna with Integrated Radiation and Scattering Performance.

In this paper, a novel design method of circularly polarized folded transmitarray antenna (CPFTA) is presented by applying sequential rotation technology. Compared with the general design method, the novel design method can reduce the design difficulty and improve the axis ratio (AR) bandwidth significantly without adding any additional structure. To verify the proposed method, both a general CPFTA (GCPFTA) and a novel CPFTA (NCPFTA) are designed, fabricated, measured and compared. Good agreements between simulated and measured results are obtained. Thanks to the creative design, the integrated radiation and scattering control of the CPFTA is realized for the first time. The proposed NCPFTA has the advantages of broadband, high gain, planar structure, low profile, convenience in installation and low radar cross section (RCS), which has potential application in mobile satellite communication.