Μέθοδοι και τεχνικές βελτιστοποίησης της απόδοσης δικτύων οπτικών επικοινωνιών

• Main Authors: Papagiannakis, Ioannis, Παπαγιαννάκης, Ιωάννης
• Format: Doctoral or Postdoctoral Thesis
• Language: Greek
• Published: University of Patras 2009
• Subjects: Δίκτυα; Οπτικά; Λέϊζερ άμεσης διαμόρφωσης; Εξισωτής; Αποκλειστικός οπτικός ημιαγωγικός ενισχυτής; Παθητικά οπτικά; Networks; Optical; Directly modulated laser; Equalizer; Passive optical; Επιστήμες Μηχανικού και Τεχνολογία; Επιστήμη Ηλεκτρολόγου Μηχανικού; Ηλεκτρονικού Μηχανικού; Μηχανικού Η/Υ; Engineering and Technology; Electrical Engineering; Electronic Engineering; Information Engineering; DML
• Online Access: http://hdl.handle.net/10442/hedi/17451; https://doi.org/10.12681/eadd/17451

Nowadays, the rapid increase in bandwidth demanding services imposes new technological directions in the design of next generation optical networks with the purpose to achieve: a) reduced cost, b) larger transmission distances, c) larger number of users and d) higher bandwidth connectivity to the end user. However, due to the analogue nature of the optical signals, the optical networks suffer from a variety of linear and non-linear impairments. These impairments have a direct impact in the signal’s bit error rate performance, while their effect increases as bit rate increases. The compensation of impairments has been traditionally performed by optical means. However, the rapid increase in available electronic processing power has made electronic mitigation of impairments a viable option, leading to an adaptive, low cost and integrated solution which avoids additional optical losses. The goal of this thesis is to study the effective mitigation by electronic means of the most important impairments (i.e. chromatic dispersion, self-phase modulation and filter concatenation) that are related with optical networks and particularly metropolitan, access and passive optical networks. From the network (and system) design point of view, this study proposes the optimum use of certain low cost solutions able to extend (in bit rate and coverage) the applicability of next generation optical networks. More specifically, the effectiveness of electronic equalization is examined for systems utilizing low cost, conventional directly modulated laser (DML) sources that are operated at 10 Gb/s. The purpose in this case is to extend the reach and operating data rate of these systems by mitigating the transmission limiting effects due to the source characteristics and the link impairments (dispersion, self-phase modulation, and filter concatenation) with the optimum use of electronic equalization. Moreover, with respect to next generation optical access networks an effective and useful design approach on PON systems is fully ...