Reflective Surfaces Based on Semi-Passive Reconfigurable Polymer Network Liquid Crystal

Future telecommunication networks demand for innovative solutions that can improve the poor coverage conditions expected at millimeter-wave frequencies (>30 GHz). The devices composing those networks, apart from improving the coverage, must be of moderate cost, easy to manufacture and operate under strict low power consumption requirements. In this paper, a reflecting planar semi-passive device based on Polymer Network Liquid Crystal (PNLC) is proposed as an example of a single-time programmable RIS. Due to the PNLC properties, the device is easy to mass-produce, can be easily programmed for each working scenario, and behaves like a passive device after it is programmed. The envisioned implementation workflow is also discussed, together with its advantages and disadvantages. Finally, a single-time programmable reflectarray antenna based on PNLCs is designed at 100 GHz from experimentally validated data, and different radiation conditions or scenarios are presented.