In the telecommunications industry, with the number of users grows, the demand for the use of fast, but cheap technologies, what is cost relatively low development and operational expense is growing. There is an example the „Filterless Optical Network” (FON), which is a kind of passive optical network.
The optic networks, which does not contain selective elements (FON), will take part in he evolving of the IP transport layer in the near future. Against the ordinary wavelength division DWDM systems with optical filters, the advantages of the FON networks are the use of cheap optical devices, the simple system engineering design and low operational cost.
In my thesis I introduce the structure and operation of the FON networks and those devices, which of the network and its nodes is built. I describe the problems of the optical signal transmission, such as physical barriers, that distort the signal over longer distance. I present a modulation process, what I used, when I solved the task, the DP-QPSK (Dual-Polarization Quadrature Phase-Shift Keying), which can be achieve a higher bit rate. Furthermore my task was to specify the system engineering of the terminal and the branching nodes of the FON networks.
My target was to model a FON point-to-point connection, which length is minimum 800 km and it contains five intermediate branching node. I had to evaluate the model in perspective the optical signal-to noise ration. I introduced in my thesis the process of the modelling of the FON link and the result, which I got with running the model.