Reis, AntónioRocha, José Ferreira daGameiro, AtilioCarvalho, José Pacheco de2019-10-292019-10-292017978-1-5090-5622-4http://hdl.handle.net/10400.6/7428This work studies a digital transmission system by fiber optic. We give special relevance to the synchronism block. The fiber is a transmission medium with large bandwidth and low attenuation. These characteristics allow high speed and long distances. The transmission, instead asynchronous, it is synchronous what provides a big efficiency of 100%. However, the synchronous transmission needs a synchronizer. The objective is to study the synchronizers and their performance of output jitter Unit Interval Root Mean Square (UIRMS) versus input Signal Noise Ratio (SNR). © University of West Bohemia, 2017engOptical Digital TransmissionSynchronismconference object