Advances in Optical Wireless Communications: From Covert Design to ORIS-Assisted Systems

This seminar presents two key advances in optical wireless communications (OWC): covert transmission design and optical reconfigurable intelligent surface (ORIS)-assisted systems. First, we propose a novel covert communication scheme for water-to-air (W2A) OWC systems, leveraging narrow signal wavebands, device characteristics and outdoor ambient radiation. Under covertness constraints, we maximize the covert throughput by optimizing signal power and blocklength, considering both scenarios where transmitter has or lacks knowledge of adversary listener’s position and optical filter parameters. Numerical results demonstrate that strong ambient radiation and narrow wavebands significantly enhance signal covertness. Second, we provide a comprehensive overview of the hardware architectures and operating principles of ORIS. We analyze ORIS deployment in free-space optical (FSO) and visible light communication (VLC) systems, discussing channel model extensions and the impact of transceiver architectures on performance enhancement. We also outline promising research directions for future ORIS-assisted OWC systems.