RZ-OOK to NRZ-OOK format conversion based on a single fiber Bragg grating

Abstract

We propose a return-to-zero on-off keying (RZ-OOK) to non-return-to-zero (NRZ) OOK conversion scheme based on a single custom-designed fiber Bragg grating (FBG). The custom-made FBG is designed and synthesized using discrete layer-peeling algorithm. It is shown that such a FBG can replace the combination of interferometer and the cascaded filter that are invariably employed together in the reported schemes for RZ-OOK to NRZ-OOK format conversion. Simulation results show that the input 20-Gb/s RZ-OOK signals with different duty cycles can be converted into NRZ-OOK signals with high Q-factor.

Theoretical study of all-optical RZ-OOK to NRZ-OOK format conversion in uniform FBG for mixed line-rate DWDM systems

“…This was performed to study the device fabrication tolerances impact on the modulation format conversion efficiency. The results are similar to the previously reported [17] for the single-channel case when slight detuning of the filter central frequency and channel central frequency could increase the signal quality. But the difference is that RZ50-OOK has better modulation format conversion efficiency comparing to the RZ33-OOK which is shown in the obtained results.…”

“…With the increasing demand for data amount, multi-channel operation seems to be integral functionality for the modulation format converters. RZ-OOK to NRZ-OOK modulation format conversion with uniform fiber Bragg gratings (FBGs) so far has been studied for a single-channel [15][16][17][18] and multichannel operations [19] for equal line-rate DWDM systems. The various interfaces used in optical networks leads also to mixed line-rate (MLR) FOTS.…”