Optimization study for the generation of high-bit-rate spectrally enriched pulses for WDM applications

Abstract

In this work a detailed analysis has been done for generating multigigahertz picosecond spectrally enriched pulses from optical double-side-band suppressed carrier signal for WDM source applications. A dual frequency signal is compressed, spectrally enriched and made pedestal free by propagating through an appropriate combination of conventional single mode fiber and/or a non-linear fiber loop mirror consisting of dispersion shifted fiber/conventional single mode fiber. Our numerical studies reveal that one can not ignore chromatic dispersion effects in non-linear loop mirror. We found that the loop mirror not only does intensity dependent shaping, but also compresses and increases the peak power due to the combined effect of optical non-linearity and group-velocity dispersion. A combination of fibers has been proposed for scaling the repetition rates from 10 to 100 GHz. In addition, individual optimum combinations of fibers for 10 and 40 GHz are also discussed. The time and frequency domain analysis along with the study of chirp of the pulse indicates that spectral enrichment is more than 10 nm, thus supporting several WDM channels with fiber combinations suggested here.