Design of a Mechanically RIS Unit Cell with Prephased States at 26 GHz

A prephased 1-bit mechanically reconfigurable unit cell for a reconfigurable intelligent surfaces (RIS) is presented. In the proposed RIS unit cell design, a geometric translation of the element has been implemented, obtaining two different pairs of RIS unit cell each with a 1-bit mechanical reconfiguration. The electromagnetic (EM) behavior is analyzed using the reflection coefficient for normal and oblique incidence, demonstrating its suitable operation in the n258 band of 5G. A 10 × 10 mechanically RIS is designed using the two pairs of unit cells and its radiation performance is compared to a conventional 1-bit RIS at 26 GHz. It is shown how a 1-bit configuration with pseudo-randomization for mechanically RIS enhances the radiation pattern performance while maintaining the simplicity of 1-bit reconfiguration.