Edfa

Resumen: Debido a la necesidad de transmitir mayor cantidad de información a velocidades elevadas y sobre grandes distancias es necesario mitigar el fenómeno de la dispersión en una fibra, el cual es un gran problema en sistemas de comunicación óptica. Una solución a este problema es el uso de solitones, los cuales mantienen la forma del pulso después de propagarse por grandes distancias. Los solitones se forman debido al balance entre los efectos dispersivos (GVD, Group Velocity Dispersion) y no lineales (SPM, Self Phase Modulation) en sistemas de comunicación ópticos basados en solitones, estos pueden ser aplicados en distancias de varios miles de kilómetros con una gran capacidad para transportar información con el uso de amplificadores ópticos. En este artículo se estudia y simula en OPTISYSTEM la propagación de los solitones a velocidades de varios Gbps a través de fibras monomodo estándar (SSMF, Single Mode Optical Fiber) y fibras monomodo de dispersión desplazada (DSF, Dispersion Shifted Fiber), en conjunto con fibras compensadoras de dispersión (DCF, Dispersion Compensating Fiber), sobre decenas de miles de kilómetros, con el objetivo de analizar su comportamiento y mejora en el desempeño de la transmisión.

Abstract: Because of the need to transmit as much information at high speeds and long distances is necessary to mitigate the phenomenon of dispersion in a fiber, which is a big problem in optical communication systems. One solution to this problem is the use of solitons, which maintain the shape of the pulse after propagation over long distances. Solitons are formed by the balance between dispersive effects (GVD, Group Velocity Dispersion) and nonlinear (SPM, Self Phase Modulation), in optical communication systems based in solitons, they can be applied in distances of several thousand of kilometers with a large capacity to carry information with use of optical amplifiers. In this article is studied and simulated in OPTISYSTEM the propagating of solitons to rates of Gbps through standard single mode fiber (SSMF, Standard Single Mode Fiber) and dispersion shifted fiber (DSF, Dispersion Shifted Fiber) as well as dispersion compensating fibers (DCF, Dispersion Compensating Fiber) over tens of thousands of kilometers, with the aim of analyzing its behavior and improvement in the performance of the transmission.

With the increasing demand and growth in optical telecommunication networks, the sensitivity of an optical receiver become an important part of telecommunication transmission networks. The unlimited bandwidth of an optical fiber create a path for large volume of signals to flow rapidly in a fraction of a seconds. This increase in the volume of transmitted signals causes severe traffic congestion, making the receiver insensitive, prolong the signal processing time and identified bits wrongly. In this research, Optisystem 7 professional software using Erbium Doped Fiber (EDF), Avalanche photodiode (APD), Non-Return-to-Zero modulation format, optimization tool and low pass Bessel filter, CW laser, pump laser, a gain flattering filter, attenuator, Bit Error Rate Analyzer (BER) etc, was used to improve the sensitivity of the receiver. The procedure of the design was to first improve on the gain using Erbium Doped Fiber Amplifier (EDFA), reduce loss and propagation time and increase the signal flow. Optisystem simulation was used to determine the optimum gain and the receiver sensitivity for several values of attenuation. This research investigated and analyzed the performance of the optical receiver at a wavelength of 1550nm, optic fiber of length 100km. Simulations were made and the Bit Error Rate analyzer values taken. Several values of Q-Factor and Bit Error Rate were tabulated and the corresponding graphs plotted. There was an improvement in the gain, quality factor, the quality of signal with a low noise value and the extended transmission or propagation time was reduced. The result of the design showed an improvement in the sensitivity of the receiver.

The gain flatness of erbium-doped fiber amplifier (EDFA) is a key device for wavelength division multiplexing (WDM) application in modern optical network systems. The purpose of this paper is to correct the gain non-uniformity for each channel in order to equalize the amplitude gain in a wavelength division multiplexing (WDM) system. The system is simulated using Optisystem software to achieve gain flatness of EDFA through optimized fiber length and pump power. The gains are flattened within 24±0.299dB from 1546nm to 1558nm band of wavelength with noise figure (NF) <6dB and bit error rate (BER) <10-9 for 16-channels simultaneous amplification in a single stage EDFA. A WDM system which includes an EDFA is modeled and obtained maximum uniformed gains.

The aim of this paper is to analyze the performance of Erbium Doped Fiber Amplifier (EDFA) system by comparing the
gains and noise figures of different commonly available EDFAs. The four stage enhancement circuit has been designed and
simulation studies for different types of EDFAs are compared by replacing different EDFAs in the four-stage enhancement circuitry of
EDFA in WDM configuration. Further, for the EDFA with comparatively better gain and noise figure spectrum, the pump powers are
varied and a comparison of gain and noise figure with respect to wavelength is carried out. Finally, the Eye Diagram and Min BER
has been generated for the best Pump Power performance.

ABSTRACT The analysis of cascaded TDFA-EDFA and EDFA-TDFA configurations has been carried out by designing and simulating optical communication system for 96 DWDM channels spaced at 0.8 nm, considering all practical parameters. The performance of the DWDM system using both hybrid fiber amplifier configurations has been analyzed separately. The simulation results showing quality factor (Q), eye diagrams, signal strengths and bit error rate (BER) at various receivers clearly demonstrate that both the configurations work satisfactorily for BER of 10-9 at 1479 nm to 1555 nm bandwidth spectrum for a span of 40 km optical fiber. It is further concluded from the performance analysis of both hybrid configurations for DWDM system that hybrid TDFA-EDFA configuration shows improved results over hybrid EDFA-TDFA configuration for 40 km span lengths in terms of BER and Q factor for 96 DWDM channels spaced at 0.8 nm in the wavelength range of 1479 nm to 1555 nm.

– In this paper the results of simulation of erbium-doped fiber amplifier (EDFA) characteristics are presented. The Gain, ASE power and Noise Figure variations of a forward pumped EDFA as functions of fiber length, injected pump power and signal input level are investigated. In this research a simulation program that solves the rate and propagation equations numerically and shows the obtained results graphically is created in MatLab. The typical EDFA physical parameters used in the simulation program for two pump wavelengths (980 и 1480 nm) are given. The optimal length of erbium-doped fiber, the pump power and the signal input power dynamic range that meet the requirements for maximum gain and minimum noise figure are determined. Резюме – В тази работа са представени резултати от симулационни изследвания на характеристиките на оптични усилватели на базата на легирано с ербий влакно (EDFA). Обекти на изследването са зависимостите на усилването, шумовата мощност от ASE и коефициентът...

ABSTRACT Optimal performance calculations in point of the gain and the pump power of hybrid amplifiers consisting of erbium-doped fiber amplifiers (EDFAs) and fiber Raman amplifiers for increasing the transmission capacity in communication systems are preformed. In the hybrid amplifier system which is formed from a single-mode EDFA, which has 18 m length, and two fiber Raman amplifiers, which have 6,5 and 7 km lengths, it is shown that the gain of 3-4 dB can be obtained for the long-wavelength applications

Performance limits of 10Gbit/s transmission over standard single mode fibre (SMF) without the deployment of in-line erbium-doped fibre amplifiers (EDFA's) are evaluated by means of numerical simulation. The fibre system was modelled using the standard split-step Fourier algorithm for the solution of nonlinear Schrodinger equation. The effect of group velocity dispersion (GVD) compensation scheme, degree of GVD compensation of the SMF, input optical powers to SMF and to the dispersion compensating fibre (DCF) has been investigated with the aim to maximize the distance between transmitter and receiver. We have found that post-compensation scheme performs better than the pre-compensation scheme and that, by careful selection of input powers and degree of GVD compensation, it should be possible to keep the bit-error-ratio (BER) bellow 10-15 for SMF length of 270 km.

RESUMO Neste trabalho são estudadas configurações de amplificadores híbridos constituídos por amplificador Raman em cascata com Erbium Doped Fiber Amplifier (EDFA) (Amplificador com fibra dopada com Érbio) com reciclagem de bombeamento residual Raman, a serem utilizados na expansão da capacidade de sistemas de comunicações óticas utilizando Wavelength Division Multiplexing (WDM) (Multiplexação por Divisão de Comprimento de Onda. Foi realizada), mediante simulação utilizando pacote comercial, análise do desempenho de diferentes configurações de amplificadores híbridos Raman+EDFA, em termos do ganho global e ondulação (ripple-variação do ganho dos canais de entrada). A flexibilidade do perfil espectral do amplificador Raman pode ser combinada com a alta capacidade de potência de saída do EDFA para obter amplificadores híbridos com banda larga. Este trabalho aplica a técnica de otimização de lasers de bombeamento de amplificadores Raman aplicada em amplificadores híbridos Raman+EDFA para aplicações em sistemas WDM. Os resultados preliminares demonstram que o amplificador híbrido Raman+EDFA com reciclagem de bombeamento residual Raman combinado com uma seleção apropriada de potências e comprimentos de onda dos lasers de bombeamento Raman, possibilita a obtenção de amplificadores híbridos banda larga com maior eficiência de conversão de potência, ganho alto e plano. ABSTRACT In this work different configurations of hybrid amplifiers are studied, made by a Raman amplifier followed by an EDFA. Such amplifiers can be used to increase the transmission capacity in optical communication systems. The performance of different hybrid EDFA+Raman amplifiers is obtained using commercial software. Their performance is analyzed in terms of the global gain and ripple. The flexibility of the Raman amplifier spectral