Performance comparison of four-wave mixing (FWM) in a single semiconductor optical amplifier (SOA) based all-optical up/down wavelength converter for advanced modulation formats (CSRZ, DBRZ and MDBRZ) on the basis of power penalties

In this article, the bit error rate (BER) analysis of four-wave mixing (FWM) in semiconductor optical amplifier (SOA) based wavelength converter is carried out for various modulation formats such as carrier suppressed return tozero (CSRZ), duo binary return to-zero (DBRZ) and modified duo binary return to-zero (MDBRZ). The performance analysis is performed at following bit rates: 10 Gbps, 20 Gbps and 40 Gbps. The power penalty of each format is determined. Lower the power penalty better is the performance. It has been noticed that CSRZ gives better performance at 10 Gbps while at 20 Gbps DBRZ performs better than the other and again at 40 Gbps line rates, CSRZ exhibits better performance as compared to two advanced modulation formats.