Applications of O-band semiconductor optical amplifiers in fibre-optic telecommunication networks

Optical ??bre communication is an essential part of modern telecommunication networks. Research activities are aiming to transport and switch information streams through optical ??bre networks most e??ciently. This thesis is devoted to applications of 1310 nm semiconductor optical ampli??ers (SOAs) in ??bre optic telecommunication networks. The basic application of 1310 nm SOAs is the ampli??cation of optical signals. In this thesis dense wavelength division multiplexed SOA based transmission in the 1310 nm wavelength domain is investigated. The 1310 nm SOAs allow high speed (10-40 Gbit/s) transmission over metro range distances (50-200 km) without any dispersion compensation in standard single-mode ??bre based networks. This is important for access and metro systems, where the system cost is shared by the limited number of users. To alleviate optical-electrical-optical conversion at the interface point between access-metro and core networks a novel wavelength conversion technique is proposed. Nonlinear polarization rotation in the 1310 nm SOA permits the realization of 1310- to-1550 nm wavelength conversion and the aggregation of multiple data streams in the 1310 nm wavelength domain into one time interleaved data stream in the 1550 nm wavelength domain. By utilizing the 1310 nm SOA in a gain transparent con??guration an all-optical optical time domain multiplexed add-drop switch was realized. The proposed adddrop switch was widely tested in the laboratory and ??eld transmission experiments allowing 160 Gbit/s transmission over 550 km of standard single-mode ??bre and the realization of a fully functional 160 Gbit/s optical time domain multiplexed network. Based on this research it is concluded that 1310 nm SOAs are versatile components which support essential transmission and switching functionalities with great opportunities for utilization in advanced telecommunication networks.