Photonic Terahertz Wireless Communication: Towards the Goal of High-Speed Kilometer-Level Transmission

From the perspective of wireless transmission distance in the terahertz-band (THz-band), the 10-100 m, 100-1000 m, and >= 1000 m ranges are recommended for indoor communications, medium-distance communications, and long-distance communications, respectively. However, most existing photonic terahertz communication demonstrations reported in previous studies have a distance of less than 100 m, with some being even shorter at 10 m or 1 m. In this study, by combining high-gain and high-sensitivity terahertz modules, as well as signal processing technology, we have successfully demonstrated transmission over 850 m with a net rate of 50 Gbit/s at a 320 GHz carrier frequency through outdoor field experimental verification. This particular demonstration represents the most significant distance-rate product, as well as the longest wireless distance achieved so far for photonic terahertz wireless communication. The results demonstrate that the integration of terahertz photonics, electronics, and cutting-edge DSP algorithms, has the potential to enable long-distance and high-speed wireless communication for frequencies >= 300 GHz. Our work represents another significant stride towards achieving our goal of realizing the world's first photonic terahertz-wave communication over kilometer-level distances.