Design and Implementation of a Millimeter-Wave Wireless Transceiver Based on a Waveguide-Fed Space-Time-Coding Metasurface

Future multimode wireless communication systems require compact, cost-effective, and flexible solutions supporting large-scale antenna arrays. Space-time-coding metasurfaces (STCMs) have emerged as a promising interface between digital signal processing and electromagnetic wave manipulation, enabling dynamic modulation of carrier waves in the time domain. Here, we present a versatile and efficient waveguide-fed space-time-coding metasurface (WF-STCM) transceiver architecture with harmonic beam-scanning and sideband suppression capabilities. The amplitude and phase of the radiated harmonics are precisely controlled by using time-varying bias signals applied to integrated PIN diodes. As a proof of concept, a WF-STCM-based wireless communication system is demonstrated by using Quadrature Phase Shift Keying (QPSK) and 16-Quadrature Amplitude Modulation (16-QAM) schemes. The WF-STCM array performs both signal modulation and reception, incorporating hybrid analog/digital signal processing. Experimental results confirm robust data transmission across the 25–29 GHz band with modulation rates reaching up to 5 MHz. Compared to conventional horn antenna-based receivers, the WF-STCM receiver demonstrates a superior signal processing capability under low signal-to-noise ratio conditions. These findings establish the feasibility of a fully metasurface-integrated wireless transceiver and provide a foundation for future scalable multinode communication networks based on metasurface-enabled architectures.