Hybrid radio-over-fiber transport system to support heterogeneous indoor mobile network environments

The recent advances in mobile network technologies are based on pioneering higher radio frequency ranges such as millimeter wave and (sub-)terahertz bands. Most likely, the simultaneous use of multiple bands of such high frequency as well as mid/low frequency ranges should be considered to implement heterogeneous mobile environments where diverse conventional and emerging applications can coexist. This study aims to propose, demonstrate, and evaluate a radio-over-fiber (RoF)-based optical transport system that meets the aforementioned future indoor network's requirements. In particular, we suggest a novel distributed antenna system architecture that can support next-generation mobile services such as millimeter wave 5G and terahertz 6G as well as commercial 5G systems employing low/mid bands. Following the experimental validation of the downlink and uplink transmission of radio signals, we investigate the cost reductions obtained by implementing the proposed system in comparison to conventional topologies such as point-to-point and wavelength division multiplexing-based point-to-multipoint connections.