N. Tihomorskis, S. Migla, D. Cirjulina and A. Aboltins, “Software Defined Radio Prototyping of Direct Detection OTFS for Optical Wireless Links,” 2026 IEEE 23rd Consumer Communications & Networking Conference (CCNC), Las Vegas, NV, USA, 2026, pp. 1-5, doi: 10.1109/CCNC65079.2026.11366447.
Abstract:
Optical wireless communication (OWC) is increasingly explored as a high-capacity, energy-efficient alternative for terrestrial and non-terrestrial links. To address challenges posed by mobility-induced Doppler shifts, orthogonal time frequency space (OTFS) modulation offers enhanced spectral efficiency and robustness, making it well-suited for dynamic OWC scenarios. This paper presents one of the first real-time software-defined radio (SDR)-based implementations of optical OTFS (O-OTFS) tailored for intensity-modulation direct detection (IM/DD) optical systems. Two modulation schemes—direct current-biased O-OTFS (DCO-OTFS) and asymmetrically clipped O-OTFS (ACO-OTFS)—were designed in MATLAB Simulink and deployed on USRP B210 radios. The SDR platform enables flexible signal generation, over-the-air prototyping, and integrated optical testing. Experimental validation confirms the feasibility of both schemes, achieving bit error ratios (BERs) on the order of 10-4, suitable for integration with standard forward error correction (FEC) schemes, demonstrating the viability of SDR-based prototyping for next-generation OWC links.