Compact Silicon-Photonics Waveguide-Confined Receiving and Transmitting Antenna With Signal Remodulation for Indoor Optical Wireless Communication

We propose and demonstrate a compact silicon photonics (SiPh)-based waveguide (WG)-confined receiving antenna (RA) and transmitting antenna (TA) integrated with an enhanced direct intensity remodulation scheme. In a narrow-beam-steered system, the RA exhibits only 5.3-dB power variation over a 12° angular range, supporting data rates > 28.12 Gbps, while in an ultra-narrow-beam-steered system, a 6-dB field-of-view (FoV) of 6.4° enables data rates > 70 Gbps. The combined RA-TA architecture supports bidirectional channels without additional UL lasers. The proposed signal interference cancellation (SIC) algorithm further enhances UL performance. Experimental results show signal-to-noise ratio (SNR) improvements up to 2.37 dB and potential UL throughput gains up to 45% for higher DL modulation depths.