Simplified coherent optical network units for very-high-speed passive optical networks

作者：Istvan Bence Kovacs, Md. Saifuddin Faruk, Pablo Torres‐Ferrera, Seb J. Savory · 发表于：Journal of Optical Communications and Networking · 年份：2024 · DOI：10.1364/jocn.514867 · 被引用次数：58 · 研究领域：Optical Network Technologies、Advanced Photonic Communication Systems、Advanced Optical Network Technologies

Future passive optical networks (PONs) for 200Gb/s/ λ , and beyond, pose a significant technological challenge. The use of coherent technology in access networks provides a great solution based on concepts from mature technologies to achieve the speeds needed for very-high-speed PON (VHSP). In this paper, we provide an overview of the currently demonstrated technologies and propose a possible simplified optical network unit (ONU) for time division multiplex PON (TDM-PON). The proposed ONU uses a single polarization heterodyne receiver, using either a balanced photodiode or a single-ended one and an electro-absorption modulated laser (EML)-based transmitter. The experimental demonstration using the proposed ONU in a bidirectional, symmetrical transmission over fiber distances of 20 km and 40 km shows the viability of the technology. The downstream direction achieves a power budget of 34.3/29.3 dB for 20 km and 33.9/29 dB for 40 km, for a balanced/single-ended receiver, whereas the upstream transmission achieves 29.3 dB for both scenarios.