Multi-objective Optimization of Amplifier Operating Point and Launch Signal Power Pre-emphasis in a Cascade of EDFAs

The determination of the optical setup for the devices to maximize transmission quality is a challenging task. In this paper, we propose to jointly optimize the operating points of the optical amplifiers in the communication link and a linear pre-emphasis in the transmitters’ launch power. We deploy a multi-objective algorithm to maximize the performance of an optical link impaired by the amplified spontaneous emission noise (ASE) and gain distortions generated by a chain of erbium-doped fiber amplifiers (EDFA), aiming to maximize the minimum OSNR in all transmitted channels and minimize the overall cascade tilt. We analyzed two scenarios with different characteristics, and the simulation results indicate that the proposed optimization scheme achieves better performance outcomes (considering OSNR and tilt).

I. Introduction

Erbium-Doped Fiber Amplifiers (EDFA) are essential devices in modern optical fiber-based transmission systems [1]. They make it possible to re-amplify the optical signal that suffers from power losses when transmitted along with the fiber. Furthermore, the optical amplifier allows the simultaneous amplification of optical signals contained in a wide spectral range, which makes its use efficient in terms of capital cost [1]. Amplifiers are usually used in a chain on an optical link. EDFAs are placed at the end of each fiber span (of approximately 80 km) to overcome the power losses imposed to the signal [1].