Investigation and Suppression of Fiber Nonlinearities Using Injection-Locking in OFDM-WDM System

Monika Nehra,Deepak Kedia

doi:10.1155/2018/8690278

Abstract

The fiber nonlinearities play a major role in optical communication with respect to the system performance and transmission capacity. Here, fiber nonlinear impairments are investigated through consideration of several parameters of optical fiber system, such as fiber length and core effective area. We also demonstrate the mitigation of fiber nonlinearities by using single-stage injection-locking in 3 × 10 Gb/s OFDM-WDM system. This paper focuses on selection of appropriate bias current for slave laser to suppress the four wave mixing (FWM) crosstalk effects. These findings resemble the importance of single-stage injection-locking for FWM suppression for high-speed data communication.

Highlights

Over the time, the requirements for bandwidth have been increased critically
The different fiber nonlinearities come into picture such as four wave mixing (FWM), self-phase modulation (SPM), cross-phase modulation (CPM), stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS)
If the FWM products fall in transmission window of baseband signals, these can give rise to crosstalk between significant channels propagating through the fiber [3]

Summary

Introduction

The requirements for bandwidth have been increased critically. The different possible solutions have come up which include architectural modifications in terms of modulator design, advance modulation formats, and integration of wireless communication with optical fiber technologies. The different fiber nonlinearities come into picture such as four wave mixing (FWM), self-phase modulation (SPM), cross-phase modulation (CPM), stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Out of these effects, the FWM and SBS processes have significant potential to alter the performance of transmission systems, even if the systems are operated using narrow linewidth single frequency lasers [1, 2]. No doubt injection-locking technique is very effective for microwave signal generation or XPM-phase noise cancellation; it can outperform other techniques in the suppression of other fiber nonlinearities . The selection of bias current for slave laser has a significant impact over the system performance in terms of suppression of FWM products

Concept of Fiber Nonlinearities

Investigation of FWM Effects

Suppression of FWM Effects using Injection-Locking

Conclusion

Conflicts of Interest