Monitoring and all-optical signal processing techniques for transparent networks

Optical networks are under constant evolution. The growing demand for dynamism require devices that can accommodate different types of traffic. Thus the study of transparent optical networks arises. This approach makes optical networks more "elegant" , due to a more efficient use of network resources. In this thesis, the author proposes devices that intend to form alternative approaches both in the state of art of these same technologies both in the fitting of this technologies in transparent optical networks. Given that full transparency is difficult to achieve with current technology (perhaps with more developed optical computing this is possible), the author proposes techniques with different levels of transparency. On the topic of performance of optical networks, the author proposes two techniques for monitoring chromatic dispersion with different levels of transparency. In Chapter 3 the proposed technique seems to make more sense for long-haul optical transmission links and high transmission rates, not only due to its moderate complexity but also to its potential moderate/high cost. However it is proposed to several modulation formats, particularly those that have a protruding clock component. In Chapter 4 the transparency level was not tested for various modulation formats, however some transparency is achieved by not adding any electrical device after the receiver (other than an analog-digital converter). This allows that this technique can operate at high transmission rates in excess of 100 Gbit / s, if electro-optical asynchronous sampling is used before the optical receiver. Thus a low cost and low bandwidth photo-detector can be used. In chapter 5 is demonstrated a technique for simultaneously monitoring multiple impairments of the optical network by generating novel performance analysis diagrams and by use of artificial neural networks. In chapter 6 the author demonstrates an all-optical technique for controlling the optical state of polarization and an example of how all-optical signal processing can fully cooperate with optical performance monitoring.

Tracing the use of Communication Technologies in Higher Education

This chapter presents a comprehensive view of the main activities and findings of a research project entitled TRACER-Portuguese Public Higher Education Use of Communication Technologies, which focused on how the information about the use of Communication Technologies in Higher Education Institutions  can be collected, systematized, processed, and deployed to stakeholders. The project was carried out between 2011 and 2014 and its main results are a consolidated proposal of an analysis model to address the use of Communication Technologies in Higher Education institutions, as well as the U-TRACER® tool. This Web-based tool provides support to the process of collecting, processing, and deployment of data related with the use of Communication Technologies in a specific Higher Education or in a group of institutions, based on institutional or geographical criteria.