Digital signal processing waveform aggregation and its experimental demonstration for next generation mobile fronthaul

L'abstract è presente nell'allegato / the abstract is in the attachmen

Design and cost performance of WDM pons for multi-wavelength users

Die rasante Verbreitung des Internet führt zu einem steigenden Bedarf an höheren Bitraten in Telekommunikationsnetzwerken. Dieser kann derzeit nur mit optischen Netzwerken erfüllt werden, insbesondere mit der Wellen¬längen¬multiplex-Technik (WDM). Viele Forschungsergebnisse weisen darauf hin, dass WDM Passive Optische Netzwerke (PON) die nächste Generation der optischen Zugangsnetze darstellen. Die Wellenlängenmultiplex-Technik beruht darauf, dass mehrere optische Kanäle mit niedrigen Bitraten über eine Faser übertragen werden und so ein WDM Signal mit hoher Bitrate erzeugen. Ziel dieser Arbeit ist die Identifizierung von neuen Architekturen, welche jedem Benutzer und jedem Dienst mindestens eine Wellenlänge zur Verfügung stellen. Neue Methoden und Modelle zur Berechnung von ein- und mehrstufigen WDM PONs werden eingeführt. Um alle technologisch realisierbaren ein- und mehrstufigen WDM PONs zu berechnen und zu analysieren wurde ein Design Tool entwickelt. Für einen flächendeckenden kommerziellen Einsatz reicht es nicht aus, funktionierende Technologien anzubieten, vielmehr müssen ökonomische Über¬legungen miteinbezogen werden. Diese Arbeit ermöglicht einen Vergleich unterschiedlicher Architekturen hinsichtlich ihrer Wirtschaftlichkeit und zielt darauf ab, jene Architekturen zu identifizieren, welche kostenoptimal sind. Neue kosten¬optimale Netzwerk-Architekturen führen zu einer schnelleren Marktpenetration und dazu, Fiber-to-the-Home (FTTH) Realität werden zu lassen.Due to the incomparable popularity of the Internet, the already enormous and still rocketing bandwidth demand may only be satisfied by optical networks, particularly by using the Wavelength Division Multiplexing (WDM) technology. In many research labs, WDM Passive Optical Networks (PON) access networks are considered as the next generation optical access. To obtain WDM signals with high bit rates, multiple channels operating at a lower transmission speed can be supported on a single optical fiber. The subject of this thesis will be engineering new cutting edge architectures offering each user and service at least one wavelength. New techniques and models are introduced to design single and multistage WDM PONs. A design tool was implemented to analyze all technologically feasible single and multistage WDM PON architectures. During real deployments, the technology has worked but the economic factors have proven to be too costly. Thus, it is important to examine these economic aspects. The objective is to identify those architectures that minimize costs. Access to these newly identified network architectures will prompt market introduction as well as market penetration helping Fiber-to-the-Home (FTTH) to become reality

Wavelength reconfigurability for next generation optical access networks

Next generation optical access networks should not only increase the capacity but also be able to redistribute the capacity on the fly in order to manage larger variations in traffic patterns. Wavelength reconfigurability is the instrument to enable such capability of network-wide bandwidth redistribution since it allows dynamic sharing of both wavelengths and timeslots in WDM-TDM optical access networks. However, reconfigurability typically requires tunable lasers and tunable filters at the user side, resulting in cost-prohibitive optical network units (ONU). In this dissertation, I propose a novel concept named cyclic-linked flexibility to address the cost-prohibitive problem. By using the cyclic-linked flexibility, the ONU needs to switch only within a subset of two pre-planned wavelengths, however, the cyclic-linked structure of wavelengths allows free bandwidth to be shifted to any wavelength by a rearrangement process. Rearrangement algorithm are developed to demonstrate that the cyclic-linked flexibility performs close to the fully flexible network in terms of blocking probability, packet delay, and packet loss. Furthermore, the evaluation shows that the rearrangement process has a minimum impact to in-service ONUs. To realize the cyclic-linked flexibility, a family of four physical architectures is proposed. PRO-Access architecture is suitable for new deployments and disruptive upgrades in which the network reach is not longer than 20 km. WCL-Access architecture is suitable for metro-access merger with the reach up to 100 km. PSB-Access architecture is suitable to implement directly on power-splitter-based PON deployments, which allows coexistence with current technologies. The cyclically-linked protection architecture can be used with current and future PON standards when network protection is required