Performance improvement of fiber-optic transmission system by replacing electronic repeaters with optical amplifiers

Abstract

We study four methods: the zero-dispersion wavelength (ZDWL) transmission, the dispersion management, the optical soliton transmission, and the midway optical phase conjugation (OPC), for upgrading installed electronic repeater-based optical fiber transmission system to optically amplified system. We derive the optimum design rules for each scheme to achieve the maximum transmission data rate. The 1,318-km-long Thailand-Malaysia (T-M) submarine fiber-optic transmission system is used as the system model. Firstly, we give the basic knowledge about fiber characteristics and their effects to signal propagation, and review the concepts of four upgrading schemes. Then, the numerical simulation is used for studying the signal distortion induced from the third-order dispersion and the Kerr effect in ZDWL transmission system. When the ZDWL transmission is employed to upgrade the T-M system with our optimum design guidelines, the possibility of increasing data rate from 560 Mbit/s to 80 Gbit/s is shown. For the dispersion management, the transmission data rate can be extended to 100 Gbit/s for single channel, and to 6 x 10 Gbit/s for multi-channel wavelength division multiplexing. However, when the soliton scheme is employed to improve the system performance, the numerical result shows the possibility of increasing data rate only to 20 Gbit/s because of nonlinear signal distortions. The highest data rate in this study is obtained from the system upgrading using the midway OPC. By following our design strategies, the possibility of increasing to 200 Gbit/s is numerically shown.