Real-time demonstration of 8 × 125 Gbit/s point-to-multipoint photonics-assisted THz-over-fiber PON based on an optical wavelength routing scheme.

The rapid development of photonic-assisted terahertz wireless communication addresses surging data traffic demands in wireless systems. However, existing research predominantly focuses on point-to-point THz links, neglecting multi-user application scenarios in optical-wireless access networks. This paper proposes and experimentally demonstrates what we believe to be a novel point-to-multipoint photonic-assisted THz-over-fiber passive optical network (ToF-PON) architecture based on optical wavelength routing (OWR). By deploying an N × N arrayed waveguide grating (AWG) at the remote node (RN), we achieve precise routing of multi-user optical carriers and local oscillator (LO) to optical network units (ONUs). To simplify ONU design, LOs are centralized at the optical line terminal (OLT) and shared with user carriers through wavelength reuse, reducing system cost. In this architecture, we successfully transmit an 8-channel real-time DP-QPSK signal over 24 km of standard single-mode fiber (SSMF) and 100 m wirelessly. The system achieves a real-time net data rate of 800 Gbit/s at 300 GHz with 15% soft-decision forward error correction (SD-FEC) overhead at a pre-FEC BER of 1.56 × 10^-2. To our knowledge, this represents the first experimental demonstration of real-time point-to-multipoint photonic-assisted THz wireless transmission exceeding 800 Gbit/s net rate in the THz band.