Reshetnikova O. The wavelength division multiplexing optical transmission systems characteristic optimization

The purpose: the optical signals distortions analysis when transmission is performed over the optical fiber, and the DWDM FOTS characteristics optimization. The object: processes of nonlinear and linear distortions of DWDM FOTS optical signals when transmission is performed over the optical cables. The subject: nonlinear and linear signal distortions which appear when using the DWDM transmission technology, and the optimization of DWDM FOTS characteristics taking into account these distortions. The scientific novelty and the practical value of obtained results. For the first time the problem of DWDM FOTS linear signal power optimization taking into account the FWM nonlinear products and optical amplifiers noise is formulated and solved. The improved channel signals power calculation depending on parameters of DWDM FOTS linear path elements is obtained. The assessment of optical signal SPM influence on DWDM FOTS efficiency parameters is obtained and the optimum signal power level of TOM is determined. The improved DWDM FOTS mathematical model which considers the ASE noise of optical amplifiers, linear and nonlinear distortions in OF, and also typical characteristics of TOM and ROM is developed. Determination of DWDM FOTS regeneration section length depending on dispersion distortions taking into account the created by the laser optical impulses form, and the transimpedance amplifier ISI in the ROM is improved. Method of TOM signal power optimization which is based on Q-factor maximization is possible to use in equipment development, at network design, equipment installation and adjustment and in educational process. The developed model allows to receive a signal eye-diagram at the input of ROM decision-making device and to determine the loss of accepted DWDM FOTS signal immunity taking into account the propagation medium dispersion distortions of a signal. Mathematical models which are developed in work can be used for the DWDM FOTS characteristics assessment at a design stage.