Studium vlivů teplotního namáhání zesilovacích vláken v OCDMA sítích

Abstract

At present time, the demands placed on transmission optical fibre networks are increasing. We can notice incessant pressure on increasing of the speed of transmission. One of the other essential demands is that optical fibre networks have to be able to bridge large distances. When a signal passes through the optical fibre, it is attenuated by a wide range of influences. Therefore, it is appropriate to include optical fibre amplifiers in the transmission path to achieve required quality of the signal at the end of the transmission path. This thesis deals with the issue regarding optical fibre amplifiers that are currently used in optical fibre networks and describes the influence of temperature on optical amplifiers. Particularly, the thesis is focused on Erbium-doped fibre amplifiers and their use in OCDMA networks. In the theoretical part, the essential theory related to optical fibre amplifiers is explained. There are described the fundamental principles and the types of optical amplifiers used in optical networks. Furthermore, the principle, types, and operation of OCDMA networks are explained. The practical part is aimed at the design and assembling of Erbium-doped optical fibre amplifier as well as at assembling of the complete workplace. The practical measurements, which were carried out at Strathclyde University in Glasgow, are also described. Subsequently, the simulations performed in Optiwave Optisystem are described. Lastly, the chapter deals with the proposal to solve or suppress changes caused by a thermal stress of erbium doped fibres. The main contribution of this thesis is new knowledge about the effect of thermal stress of different types of doped fibres in OCDMA network and the effect of thermal stress of doped fibres on the behaviour of OCDMA network.