Next generation technologies for 100 Gb/s PON systems
Dalla Santa, Marco
University College Cork
The worldwide explosion of Internet traffic demand is driving the research for innovative solutions in many aspects of the telecommunication world. In access systems, passive optical networks (PONs) are becoming the preferred solution towards which most providers are migrating thanks to the unrivalled bandwidth they can offer. PON systems with a capacity of 100 Gb/s are envisioned as the solution to the dramatic increase in bandwidth and will be essential to support the future fixed and mobile broadband services. However, many challenging aspects have to be addressed in order to overcome the limitations imposed by the physical layer while meeting the economical requirements for mass deployment. In this thesis a comprehensive approach is taken in order to address the most compelling problems and investigate a series of solutions to the current capacity limitations of PONs. Advanced modulation formats are used to achieve bit-rate enhancement from 10 Gb/s to 25 Gb/s re-using the same optoelectronic devices in order to provide a 2.5x increase in transmission speed without resorting to a newer, more expensive generation of higher speed devices. The management of chromatic dispersion is also addressed in order to extend the reach of the networks beyond the standard 20 km using either electronic or optical based compensation strategies. Transmission of 25 Gb/s traffic over fibre lengths of 40 and 50 km is demonstrated confirming the suitability of the proposed technologies for extended reach networks which could greatly reduce the number of existing nodes and hence the capital and operational costs of PONs. Optical amplification strategies are also discussed as a means to improve the physical reach of the networks, both in terms of distance and number of customers. Raman amplifiers and semiconductor optical amplifiers are investigated in order to extend the reach of a PON upstream channel. The results demonstrate a reach of up to 50 km which is more than double the typical fibre length of 20 km adopted in deployed systems today. A number of customers, up to 512, was also demonstrated in a 20 km network, increased from the typical 32 or 64 users of most commercial networks.
Optical access networks , Passive optical networks , Advanced modulation formats , Chromatic dispersion compensation , Burst-mode optical amplification
Dalla Santa, M. 2019. Next generation technologies for 100 Gb/s PON systems. PhD Thesis, University College Cork.