Electronics and Electrical Engineering

A Wavelength Division Multiplexing (WDM) system is a high-speed optical transmission system that simultaneously transports optical signals of different wavelengths over a single optical fiber. WDM was developed as a next generation optical signal transport technology after traditional Time Division Multiplexed (TDM) systems offering much greater potential capacities. TDM is the most popular technology in the electrical networks, but it cannot utilize the available bandwidth, because it is limited by the speed of the time-multiplexing and demultiplexing components. That technology uses electrical components, which restrict potential resources of optical fibers. The latest version of WDM, High Density WDM (HDWDM), achieves higher capacity by dividing a wavelength-band into even more channels. Today’s HDWDM systems can combine up to 128 or more wavelengths onto a single fiber [1]. Theoretically WDM technology gives indefinitely many resources in optical fibers. How much resources are dependent on many factors: channel spacing between multiplexing channels, modulation types, and optical fiber lengths (optical fiber span can be restricted by attenuation or by dispersion) [1]. This work contains the research of optical signal wastages and practical connectedness between signal transmission speed and losses. Researches are created with WDM optical link simulation contribution, where the different modulation types, signal bit rates and nonlinear effects (Self Phase Modulation SPM, Cross Phase Modulation XPM and Stimulated Raman Scattering SRS) are presented. SPM and XPM are described by Schrodinger nonlinear equations and SRS by numerical integration with the trapeze rule help [2].