Measurement-Based Characterization of Subterahertz Metasurfaces Designed to Work in a 300-GHz Band: Suitability for broader band communication in 6G

Subterahertz (sub-THz) wireless links are investigated on small and thin metamaterial structures as part of an antenna measurement system. In order to realize the device under test (DUT) at 330 GHz beyond the millimeter-wave bands, Schott glass as ultrathin glass (UTG) is chosen as the substrate more than Teflon and laminates, and it goes through the sputter deposition of a metallic thin-film process to form a pattern on its surface as the metamaterial. The signal strength at the receiver (RX) antenna for the line-of-sight (LoS) becomes weaker when the glass analogous to the phone display or room window is in between the transmitter (TX) and the RX. This problem is circumvented by placing the metallic patterned glass metamaterial in the signal path from the TX to the RX. The wireless links for cases of the LoS, the glass plane inserted, and the metasurface inserted in the propagation axis are constructed, and their electromagnetic (EM) functions are experimentally characterized. The degradation in S 21 is increased by more than 3 dB, both in simulation and measurement. In conjunction, the 64-QAM constellation as a communication standpoint of indicator of 6G mobile is evaluated in the three cases, revealing positive effects of the sub-THz metamaterial surface.