Low-cost large-area 100 GHz intelligent reflective surface: electrically column control of screen-printable high phase changing ratio vanadium dioxides

In this paper, we propose for the first time 100 GHz intelligent reflective surface (IRS) using screen-printable, high phase changing ratio vanadium dioxide (VO2). Sub-THz communications offer advantages such as ultra-high speed and ultra-low latency, it increases communication challenges due to path losses and non-line-of-sight (NLOS) problems. IRS is a representative solution to this NLOS problem. Conventional IRSs using PIN and varactor diodes have difficulty covering the sub-THz band due to the operating frequency limitations of these tuning elements. In this study, we successfully applied screen-printed VO2 switches to sub-THz IRS to control the reflection angle. The screen-printed VO2 achieved the highest reported available phase-changing-ratio (PCR) of 1,000, increasing design freedom. The measurement results are consistent with the numerically calculated values and EM simulation results. We believe that this solution will open new avenues and potential for practical applications in low-cost, large-area tunable RF electronics in the sub-THz band.