Optimized transmitter module for NRZ-duobinary in long-haul optical transmission link

In this work we present a comparative analysis of three different NRZ-duobinary transmitter modules made of either push–pull configuration based on dual arm MZIM or delay-and-add circuit based single arm MZIM or a duobinary filter followed by single arm MZIM in an ASE-noise-limited 10 Gbps optical link. The performance of all three transmitter modules has been optimized for modulator chirp and extinction ratio. These optimized transmitter modules have been further investigated to observe which transmitter-generated pulse offers comparatively better tolerance to impairments induced by group velocity dispersion (GVD) and self phase modulation (SPM). Simulative analysis reports that delay-and-add circuit based single arm MZIM transmitter module outperforms the other two transmitter modules and hence can be treated as the optimized transmitter module for NRZ-duobinary in long-haul optical transmission link.