Conductive Fabric-Based Reconfigurable Intelligent Surface

Reconfigurable intelligent surfaces (RISs) are positioned to be a key enabling technology for next-generation wireless systems. However, for RIS to become pervasive in future systems will require new technologies to unobtrusively integrate them in everyday objects (e.g., carpets, drapes, upholstery) rather than exclusive use of printed circuit boards (PCBs). In this paper, we presented a proof of concept prototype of a fabric-based RIS for internet of thing (IoT) applications. The proposed RIS is a two-dimensional surface with 6 × 9 conductive fabric elements placed on a non-conductive fabric to operate at 2.4 GHz. Each element acts as a radio frequency (RF) switch to either let the signal through (i.e., "lens") or reflect it (i.e., "mirror") to, for example, enable a legitimate link or impair an eavesdropping link. This concept of the RIS is validated in an indoor test, where the proposed fabric RIS prototype provides a 16 dB decrease in received power when the elements in adjacent columns are electrically connected to reflect the incident waves as compared to the case where the elements are electrically isolated to allow signal transmission.