Efficient 100-Gb/s wide multi-band RoF system using single-drive MZM with bias-controlled chirp parameter for 6 G indoor network

The explosive growth of mobile data traffic and the demands of 6 G networks for ultra-high data rates and low latency necessitate advanced infrastructure solutions. One promising approach is the implementation of radio-over-fiber (RoF)-based distributed antenna systems (DAS), which can efficiently transmit radio frequency signals over optical fiber, especially in dense indoor environments. However, analog RoF systems face challenges, including noise, nonlinearities, and power fading caused by chromatic dispersion. This study demonstrates a RoF-based DAS network that successfully transmits a 100 Gb/s wide multi-band signal (6 × 3.11 GHz) over 7-km standard single-mode fiber in the C-band. We suggest an efficient method for mitigating power fading by controlling the chirp parameter of a single-drive Mach-Zehnder modulator (MZM) through adjustments to the DC bias voltage. After experimental validation, we further examine the system tolerance to variations in transmission distances. These results indicate that RoF-based DAS networks, using a single-drive MZM, are well-suited for deployment in short-reach 6 G indoor applications, offering a scalable and efficient solution to meet future data demands.