EDFA gain stabilization with fast transient behavior by use of a semiconductor optical amplifier (original) (raw)

EDFA gain transients: experimental demonstration of a low cost electronic control

IEEE Photonics Technology Letters, 2003

EDFA gain transients are dynamic performance-degrading effects that need to be effectively suppressed in next-generation reconfigurable optical networks. In this paper, we experimentally assess the feasibility of an electronic dynamic gain control based on low-cost optoelectronic components, showing that a linearized electrical circuit and a control bandwidth smaller than 1 MHz can achieve the same performance as the commonly proposed all-optical feedback solutions.

Suppression of Transient Gain Excursions in EDFA’s

IFIP International Federation for Information Processing, 2005

In this paper a comparative study of two pump control schemes for suppressing transient gain excursions in EDFA's is presented. The first control scheme is based on the traditional feedforward/feedback control, while the second scheme is new and uses multiplication to combine the feedforward and feedback blocks. The controller parameters are designed using linearised (small-signal) EDFA model derived from the nonlinear state-space model of Bononi and Rusch. When the controller design is applied to the nonlinear EDFA plant, the new scheme is shown to display some important performance improvements over the traditional scheme.

All-Optical Gain Controlled EDFA: Design and System Impact

2004

An erbium doped fiber amplifier with automatic gain control was designed using the all-optical gain control technique. The amplifier performance for different control channel wavelengths and feedback loop attenuation values was experimentally investigated under static and dynamic conditions by measuring the bit error rate of a 2.5-Gb/s 8-channel DWDM system.

An Adjustable Gain-Clamped Semiconductor Optical Amplifier (AGC-SOA)

Journal of Lightwave Technology, 2000

The operation of a semiconductor optical amplifier (SOA)-ring laser-based subsystem, with the capability to provide adjustable gain-clamped operation, will be described, and preliminary characterization results will be presented. The device uses two SOAs in a ring-cavity topology: one to amplify the signal and the other to control the gain. This type of subsystem finds applications in packet-based dynamic systems where

All-Optical AGC of EDFA Based on SOA

IEEE Journal of Quantum Electronics, 2000

We propose a novel all-optical method for automatic gain controlling of transients in erbium-doped fiber amplifiers (EDFAs) using a semiconductor optical amplifier (SOA)-based negative feedback loop for adjusting the EDFA pump power. A dynamic model for the EDFA-SOA system is developed and used for numerical simulation of the transient behavior of this system. Simulation results for EDFA-SOA performance of the proposed method are presented. It is shown that using this method, it is possible to significantly reduce the transient effects, without producing power oscillations on the surviving channels.

Gain stabilization in gain clamped EDFA cascades fed by WDM burst-mode packet traffic

IEEE/OSA Journal of Lightwave Technology, 2000

This paper studies via simulation the stabilizing effect of all-optical gain-clamping (AOGC) in a chain of erbium-doped fiber amplifiers (EDFA) fed by wavelength-division multiplexing (WDM) burst-mode packet traffic. AOGC is necessary to suppress swings of output power and optical signal-to-noise ratio (OSNR). A case study is selected, in which only the first EDFA in a cascade of six amplifiers is clamped using a ring laser configuration. A numerical model which solves the transcendental equation for the average inversion at each EDFA is used for the analysis. The traffic is generated on the eight WDM channels by ON-OFF time-slotted sources, with statistically independent ON and OFF durations, randomly generated by a truncated Pareto distribution with infinite variance. The simulation model includes the generation of amplified spontaneous emission within each amplifier and the propagation of the lasing power generated in the AOGC EDFA through the cascade. It is shown that the sizable power and OSNR swings arising in an unclamped cascade of EDFA's can be effectively suppressed when a lasing signal a few decibels above the aggregate signal power develops in the AOGC EDFA and propagates along the cascade.

Experimental and theoretical analysis of relaxation-oscillations and spectral hole burning effects in all-optical gain-clamped EDFA's for WDM networks

IEEE/OSA Journal of Lightwave Technology, 1998

Experimental and theoretical analysis of the gain dynamics of all-optically stabilized multichannel erbium-doped fiber amplifier (EDFA) and the impact on wavelength division multiplexed (WDM) networks performance requirements is presented. In particular, we focus on precise analysis of the detailed transient response of the surviving channel and the relaxation oscillations of the compensating (lasing) signal. The main objective of this work is to experimentally and theoretically analyze and examine some of the critical factors such as, lasing wavelength, gain recovery time, relaxation oscillation frequency of the feedback loop, and the number of channels dropped/added, that affect the transient power excursions in the surviving channel. First, we consider the applicability of laser automatic gain control (AGC) to control fast power transients in WDM optical networks and reports the first high resolution measurements of transients in such gain controlled EDFA's. Second, the experimental results are compared with those predicted from a numerical simulation of the dynamic of the gain controlled EDFA. Index Terms-Optical amplifiers, wavelength division multiplexed networks.

Gain recovery dynamics in semiconductor optical amplifier

Optics Communications, 2001

We develop a time-domain model for gain recovery dynamics in a semiconductor optical ampli®er (SOA). This model allows to explain the gain overshoot which can be observed in the temporal dynamics of SOA gain after the crossing of a short saturating pump pulse. We show the good agreement between experimental and numerical results. Ó