Optical access networks for fixed and mobile applications [Invited Tutorial]

Optical access networks are playing a more critical role in providing diverse emerging applications for human- and machine-type communications. With the ever-growing demand for higher capacity, higher fidelity, and massive connections, numerous innovative transmission schemes and digital signal processing algorithms have been proposed in a cost-effective way. Here, we focus on two main scenarios, namely, fixed and mobile access. For the fixed access network, the solutions are categorized into direct detection, simplified coherent detection, and self-coherent detection. For the mobile fronthaul, we classify the schemes according to the functional split, including the analog radio-over-fiber, common public radio interface (CPRI), enhanced CPRI (eCPRI), and integrated and hybrid digital/analog-over-fiber interfaces. This tutorial provides an overview of the enabling technologies for fixed and mobile applications in the fifth-generation (5G) era and beyond.