Simple and robust link design concept for long haul transmission using equalization techniques

In this work we investigate the impact of adaptive electrical equalizers in long haul optical transparent transmission links (up to 800 or 1600 km). Electrical equalization has the potential to effectively compensate for distortions caused by chromatic dispersion or self phase modulation and therefore making transmission systems very robust. This will simplify the design and installation of new systems. By intensive numerical simulations we show how the application of receiver-sided equalizers can be used to simplify the dispersion management of optical transparent links, where only DCF-modules with limited compensation range are used. These DCF-modules can compensate only for 80, 20 or 5 km SSMF, respectively and distortions caused by this compensation mismatch will then be equalized at the receiver. By random distributed amplifier spacings it is shown, that even simple electrical equalization leads to an increased system performance in systems with direct detection and the aforementioned dispersion compensation mismatch.