Effectiveness of Modulation Formats to Nonlinear Effects in Optical Fiber Transmission Systems Under 160 GB/s
Haider J. Abd
Alaaldin H. Jaber
Abdulrasul A. Al-Haider
Four wave mixing (FWM) in optical fiber is unwanted effect to an optical transmission system, which can severely limit the wavelength division multiplexing (WDM) and lower the transmission efficiency. In this work, the robustness of normal Non-Return-to-Zero (NRZ), Return-to-Zero (RZ) and Modified-Duobinary-Return-Zero modulation (MDRZ) to FWM have been evaluated. Furthermore, the system performance is evaluated with the effect of fiber length tuning and applying 160 Gb/s data rate. The findings show that the RZ modulation offers a lower FWM power of -44 dBm at 700 km fiber length than -30 and -38 dBm of NRZ and MDRZ respectively at the same fiber length. In terms of system performance at the first channel and 700 km distance, the minimum BER is observed in normal RZ modulation, equal to 1.2×10-23. It is also noticeable that if NRZ and MDRZ modulations are applied, the system performance will be quickly changed and get worse, where the BEARs are increased to 1.3×10-6 and 1.3×10-8 consecutively at same channel and parameters.