Design and control techniques of optical networks

The world of communication has changed quickly in the last decade resulting in the the rapid increase in the pace of peoples’ lives. This is due to the explosion of mobile communication and the internet which has now reached all levels of society. With such pressure for access to communication there is increased demand for bandwidth. Photonic technology is the right solution for high speed networks that have to supply wide bandwidth to new communication service providers. In particular this Ph.D. dissertation deals with DWDM optical packet-switched networks. The issue introduces a huge quantity of problems from physical layer up to transport layer. Here this subject is tackled from the network level perspective. The long term solution represented by optical packet switching has been fully explored in this years together with the Network Research Group at the department of Electronics, Computer Science and System of the University of Bologna. Some national as well as international projects supported this research like the Network of Excellence (NoE) e-Photon/ONe, funded by the European Commission in the Sixth Framework Programme and INTREPIDO project (End-to-end Traffic Engineering and Protection for IP over DWDM Optical Networks) funded by the Italian Ministry of Education, University and Scientific Research. Optical packet switching for DWDM networks is studied at single node level as well as at network level. In particular the techniques discussed are thought to be implemented for a long-haul transport network that connects local and metropolitan networks around the world. The main issues faced are contention resolution in a asynchronous variable packet length environment, adaptive routing, wavelength conversion and node architecture. Characteristics that a network must assure as quality of service and resilience are also explored at both node and network level. Results are mainly evaluated via simulation and through analysis.

Progetto e realizzazione del sistema di gestione autonoma del volo e controllo in remoto per un velivolo UAV ad ala rotante

This PhD thesis presents the results, achieved at the Aerospace Engineering Department Laboratories of the University of Bologna, concerning the development of a small scale Rotary wing UAVs (RUAVs). In the first part of the work, a mission simulation environment for rotary wing UAVs was developed, as main outcome of the University of Bologna partnership in the CAPECON program (an EU funded research program aimed at studying the UAVs civil applications and economic effectiveness of the potential configuration solutions). The results achieved in cooperation with DLR (German Aerospace Centre) and with an helicopter industrial partners will be described. In the second part of the work, the set-up of a real small scale rotary wing platform was performed. The work was carried out following a series of subsequent logical steps from hardware selection and set-up to final autonomous flight tests. This thesis will focus mainly on the RUAV avionics package set-up, on the onboard software development and final experimental tests. The setup of the electronic package allowed recording of helicopter responses to pilot commands and provided deep insight into the small scale rotorcraft dynamics, facilitating the development of helicopter models and control systems in a Hardware In the Loop (HIL) simulator. A neested PI velocity controller1 was implemented on the onboard computer and autonomous flight tests were performed. Comparison between HIL simulation and experimental results showed good agreement.