Fabrication and Evaluation of Piezoelectric-Actuated Reconfigurable Liquid Metal-based Reflecting Surface for 6G Communications.

Waves in the sub-THz band (100-300 GHz) envisioned for 6G travel in very straight (rectilinear) lines, making it difficult for these waves to reach devices that are not in a base station's line of sight (LoS). Reconfigurable reflecting surfaces (RRSs) are expected to dynamically switch these narrow sub-THz beams towards the intended direction, extending the coverage and speed while providing significant cost reductions in place of base stations. Since conventional reconfigurable technologies using lumped elements suffers from low efficiency and limited steering angle, the fluidicbased technology emerged as one of the most promising solutions for the sub-THz band due to its unique reshaping capability. This proposal aims to fabricate and evaluate actuation of liquid metal filled unit cells of RRS using piezoelectric actuators. Channels and encapsulations containing liquid metal will be designed into unit cells and a low voltage will be applied to piezoelectric plates to electrically modify the unit cell’s dimensions. All the measurements conducted in ITEE labs will be recorded (as a video demo) and made publicly available (such as university website etc.). Upon the completion of this research, results and prototypes will be promoted to companies such as Nokia, Ericsson, etc., for a joint BF co-creation application. It is envisioned that the proposed method is simple, low-cost and provides significant improvement over existing methods, which will then accelerate the rollout of 6G, digitalization of economy, society, and sustainability.