Erbium-doped Fiber Amplifier Configuration Research Articles

Channel power equalization based on joint optimization of EDFA and ROADM configuration in open optical network.

Deterioration of the signal-to-noise ratio (SNR) is an important challenge in ultra-long multi optical line system (OLS) optical transmission systems. The non-uniform gain and cascading of the Erbium-doped fiber amplifier (EDFA) lead to SNR deterioration in transmission systems. In this paper, we propose two channel power equalization methods based on joint optimization of EDFA and Reconfigurable optical add-drop multiplexer (ROADM) configurations: 1) reinforcement learning (RL)-based channel power equalization (RL-PE) and 2) covariance matrix adaptive evolution strategy (CMA-ES) channel power equalization (CMA-PE). The simulation results indicate that the power equalization effect was improved by 1.9 dB through the CMA-PE method, while the RL-PE method led to a 1.5 dB improvement in an ultra-long 80-channel 7-OLS transmission system.

Performance improvements by dynamic amplifier reconfigurations for C + L-band optical networks in the presence of stimulated Raman scattering

C+L-band optical networks suffer from transmission impairments including amplified spontaneous emission noise and Kerr-induced and stimulated-Raman-scattering-induced nonlinear interference. The generalized signal-to-noise ratio (GSNR) profiles across different links of the network play a crucial role in determining the overall network traffic load and operating margins, but the GSNR is highly dependent on the signal power profiles along the link and time-varying channel-loading conditions, particularly for future dynamic mesh networks. As the network is dynamically loaded, we monitor the GSNR across the active channels of each link and investigate the benefits of regularly reconfiguring the erbium-doped fiber amplifier (EDFA) gain and tilts to optimize either (1) the mean GSNR minus the GSNR standard deviation (i.e., to achieve a high and flat GSNR across channels) or (2) the minimum GSNR to improve the traffic load and/or GSNR margins. Different lightpath provisioning strategies are studied, and simulation results for COST 239, a German network, and a sample Alibaba production network show that, compared with static EDFA configurations assuming fully loaded conditions, the GSNR margin and hence network robustness with dynamic EDFA reconfigurations can be improved by at least 0.45, 0.57, and 0.72 dB, respectively, with similar or better network blocking probability. Alternatively, the improved GSNR profiles can enable an average network capacity improvement of at least 9%, 8%, and 16%, respectively, in principle when operating at the same GSNR margin at 30% spectral occupancy.

SKKL PERFORMANCE ANALYSIS OF SUBMARINE CABLE COMMUNICATION SYSTEM (SKKL) EDFA - SOA AMPLIFIER LINK JAVA – BALI USING OPTISYSTEM

The Submarine Cable Communication System (SKKL) is a communication backbone that is deployed under the sea that used to connect networks between islands and between countries. DWDM (Dense Wavelength Division Multiplexing) technology can support long distance communication. Repeater used to reduce the impact of loss, on the detector side the signal can be detected properly. EDFA (Erbium Doped Fiber Amplifier) and Semiconductor Optical Amplifier (SOA) amplifiers can minimize the impact of loss and increasing the gain of each amplifier. The EDFA (Erbium Doped Fiber Amplifier) is an optical amplifier that can work at a wavelength of 1550 nm which provides amplification for the input signal that passes through it which is doped with the element erbium (Er). SOA amplifier is an optical amplifier that utilizes cavity or room cavity to strengthen light. By using branching unit configuration and repeaterless, repeatered, and parallel in-line amplifier configuration and optical system software 7.0 with system reliability parameters such as Q-factor, Bit Error Rate, Power Receiver, and Signal to Noise Ratio with power variations (0 dBm, 2 dBm, 4 dBm, 6 dBm, 8 dBm) at a frequency of 100 GHz for 10 channels. The best result on the Q-Factor parameter is 15,928, the BER parameter is 5.87 x 10-057, the receiver power parameter is -10,319 dBm, and the SNR is 42,713 dB. In this research the best value obtained in the Parallel in-line configuration. So as the best average is in the Repeatered EDFA configuration.

Numerical analysis of pump-signal-direction effect on the performance of EDFA systems

PurposeThe purpose of this study is to develop new tandem configurations of erbium-doped fiber amplifier (EDFA) using all possible pump-signal-direction schemes in simulation to identify a system configuration with the best performance in the means of the highest gain with the lowest noise figure (NF) output.Design/methodology/approachThe spatial evolution of the physical properties such as gain, NF, population density and amplified spontaneous emission along the total length of the double-stage single-pass EDFA and single-stage double-pass EDFA configurations under all possible pumping direction schemes was investigated. Giles and Desurvire method was used for the mathematical modeling of these configurations where the two level coupled system model equations was solved in MATLAB. In the simulation of the all proposed configurations, an input signal of −35 dBm at the wavelength of 1550 nm and a total of 14 mW pump power at the wavelength of 1480 nm was used for a consistent analysis.FindingsThe numerical value of the results obtained is specific to the input parameter values used in the simulations; however, configuration-wise, the EDFA systems found with the best performance are not parameter specific.Originality/valueThe results of this numerical work will help future experimental research of designing and developing ultra-efficient EDFA systems.

A Comparative Study and Radial Performance Evaluation for Reflective EDFA Configurations with Optimized Intrinsic Parameter Sets

For the improvement of Gain and Reduction in Noise Figure, a range of Erbium Doped Fiber Amplifier (EDFA) based configurations from simple Single Pass (SP) EDFA to Quadruple Pass with Filter (QPF) EDFA have been investigated. Modified Giles model for rate and propagation equations has been proposed and subsequently used for Gain and Noise Figure evaluation for all configurations. The influence of EDFA based configurations on its internal design parameters is investigated to obtain an optimum design parameter set. Among the single stage EDFA configurations, Reflective Double pass with Filter (DPF) with a high optimum Numerical Aperture gives good radial performance with high signal overlap factor of 0.563 and Pump overlap factor of 0.834. For the dual stage configurations, second stage of Reflective QPF EDFA gives best signal overlap of 0.6727 and pump overlap of 0.8827, whereas it has the lowest pump threshold of 0.47 mW, hence highest pumping efficiency. At 1550 nm of input signal wavelength, maximum gain of 27.66 dB and low Noise figure of 5.4 dB was obtained in QPF EDFA at lowest pump power of 20 mW. Thus QPF EDFA is suitable choice for preamplifier applications at 1550 nm.

Simulative Analysis of Inter-Satellite Optical Wireless Communication (IsOWC) Link with EDFA

Abstract In this paper, simulative analysis and performance comparison of different EDFA (Erbium-doped fiber amplifier) configurations in a 10 Gbps inter-satellite optical wireless communication (IsOWC) link have been reported for a 5,000 km long link and 1,550 nm operating wavelength. The results show that system in which both pre-amplifier and booster amplifier stages are implemented simultaneously outperforms systems with only pre-amplifier and booster amplifier stage. From the results, it can be seen that by deploying a transmission power level of 15 dBm, a link distance of 9,600 km can be achieved with a quality factor of 6.01 dB and BER (Bit error rate) of 1.07 × 10 − 9 $$1.07 \times {10^{- 9}}$$ . Also, in this paper, the performance of an 8×7 Gbps WDM-IsOWC link has been reported. The results show that by using both EDFA pre-amplifier and booster amplifier stages, a link distance of 8,000 km for each channel is achievable with desired performance levels (Q≥6 and BER≤ 10 − 9 $${10^{- 9}}$$ ). Also, the effect of channel spacing on the performance of WDM-IsOWC link is investigated. The results show that the received signal has acceptable performance levels when the channel spacing is 100 GHz but when the channel spacing is reduced to 80 GHz, the quality of the received signal degrades and link distance decreases.

Performance comparison of pre-, boost-, and inline-multimode erbium-doped fiber amplifier configurations to boost mode-division multiplexed multimode fiber link

The performance of 3×3, 4×4, 5×5, and 6×6 optical multi-input multioutput (MIMO) mode-division multiplexed multimode fiber (MMF) systems has been investigated using pre-, boost-, and inline-multimode erbium-doped fiber amplifier configuration methods with LPlm (linearly polarized) modes. The outcome of these configurations has been compared in terms of quality factor (Q-factor) and bit error rate (BER). It is reported that inline-configuration provides best results for all MIMO mode-division multiplexing (MDM) systems covering transmission distance of 100 km with acceptable BER ( 10 dB) over MMF link to boost performance of MDM system.

Review of Erbium-doped fiber amplifier

Data communication systems are increasingly employing optical fiber communication systems (OFCS) as the transmission paths for information. Various types of optical amplifiers have been developed in OFCS to amplify optical signals. In particular, the Erbium-doped fiber amplifier (EDFA) is one example of an optical fiber amplifier that is widely known for use in amplifying optical signals. The most significant points in any optical amplifier design are gain and noise figure (NF). They are closely related to each other. Low NF and high gain are the main features for optimum amplifier (Desurvire, 1987). On the other hand, the gain and NF have very strong impact with EDFA’s configurations. Therefore, changes in EDFA’s configuration play very important role during the designing of optical amplifier. The literature shows that there is no study that has been done to review the EDF configuration. Therefore, in this paper we are presenting an overview of most of the EDFA’s configurations that have been proposed in order to provide the researchers with a clear view of what has been done in this field. Key words: Communication system, optical amplifier, EDFA configurations, noise figure, gain amplifier, rare-earth doped fibers, atomic systems, EDFA’s position.

High Side-Mode Suppression Ratio Optical Pulses Generated From a Self-Seeded Fabry–Perot Laser Diode Locked by a Linear Erbium-Doped Fiber Laser

A new configuration of self-seeding scheme has been developed for wavelength-tunable optical pulse generation. In the system, an erbium-doped fiber laser is used to provide a strong wavelength seeding power and as a result, an extremely high side- mode suppression ratio of larger than 50 dB over the whole wavelength-tuning range of 13 nm can be obtained, with good pulse stability. When compared with other erbium-doped fiber amplifier configurations reported previously, the developed system exhibits higher pump efficiency and signal amplification capability. The system is simple, robust, and of low cost.

The L-band EDFA of high clamped gain and low noise figure implemented using fiber Bragg grating and double-pass method

The L-band erbium-doped fiber amplifier (EDFA) of low noise figure and high clamped-gain using gain-clamped and double-pass configuration is presented in this paper. A total of five different configurations of EDFAs by reflection scheme with single forward pumping schemes are examined and compared here. Among these configurations, we first find the configuration of 1480-nm pumped L-band EDFA with optimum gain and noise figure value. To further minimize the gain variation, a fiber Bragg grating (FBG) with 1615-nm center wavelength and 1-nm bandwidth is determined and added in double-pass L-band EDFA. The gain variation and maximum noise figure of EDFA while channel dropping is investigated. As the number of channel dropping from 32 to 4, the L-band type-A EDFA keep the variation of gain within 2.9dB and the maximum noise figure below 5dB with each channel’s input power of −23dBm.

Long wavelength band erbium-doped fiber amplifier with a reflective type first-stage amplifier

We propose and demonstrate a long wavelength band (L-band) erbium-doped fiber amplifier configuration for enhanced amplifier performance. A reflective type first-stage amplifier is accommodated in the configuration to obtain strongly amplified spontaneous emission and to use it as a pump for the second-stage amplifier. 36.5 mW of ASE power, for example, could be obtained from the reflective type amplifier, which was 5.3 mW stronger than that from a single pass type amplifier under the same experimental condition. From 3.5 to 1 dB of small signal gain improvement in wavelength range of 1570–1600 nm and 2.5 dB improvement in saturated output power for 3 dB gain compression could be achieved at 112 mW of pump power.

Serial topology of wide-band erbium-doped fiber amplifier for WDM applications

We analyze the recently proposed serial topology of a wide-band erbium-doped fiber amplifier (EDFA) covering both the C- and L-bands and compare it with the parallel configuration of C-band and L-band amplifiers. The analysis is based on an application of a comprehensive large-signal numerical model, which takes into consideration propagation of wavelength-division multiplexing (WDM) signals, bidirectional pump, and both the downstream and upstream ASE power spectral components. We have found that in the multiwavelength regime the new topology can provide output power of 3 dBm/channel for 32 C-band and 40 L-band, 0.8-nm-spaced signals with reasonable pump powers to the first and the second stage. In comparison with the usual parallel configuration of C-band and L-band EDFAs, this topology saves about 20% of overall pump power, 10% of the necessary length of erbium-doped fiber (EDF) and achieves lower noise figure for L-band signals.

Optimum configuration and design of 1480-nm pumped L-band gain-flattened EDFA using conventional erbium-doped fiber

We theoretically investigate optimum configurations of 1480-pumped L-band (1570–1610 nm) gain-flattened erbium-doped fiber amplifier (EDFA), using conventional erbium-doped fiber, for multi-wavelength wavelength division multiplexing (WDM) systems. The design criterion of L-band EDFA is to achieve the highest channel output power while keeping the differential channel output power to be ≤0.7 dB among 32 digital baseband channels with low channel noise figure of ≤5.5 dB. A total of nine L-band EDFA configurations are examined and compared. These configurations considered include the dual-forward, dual-backward, and different bi-directional pumping schemes, each with and without the midway optical isolator. Among all configurations, we find that the pump-passed case in forward-and-backward pumping scheme is the best amplifier configuration to offer the highest channel output power with good channel gain uniformity and moderate low noise figure. In addition, the tolerance of the ratio of first-staged EDF length to the total EDF length, and the effects of optical isolation of midway isolator, and pump power degradation on the characteristics of the best configuration are also examined. This investigation provides the EDFA configuration selection for multi-wavelength WDM L-band lightwave systems.

Optimum configuration and characteristic comparisons of multiwavelength erbium-doped fiber amplifier for hybrid digital/analog WDM systems

We theoretically investigate various configurations of erbium-doped fiber amplifier (EDFA) for simultaneously amplifying AM-VSB analog CATV signal and multiple optical digital baseband signals in hybrid wavelength-division multiplexing (H-WDM) systems. The design criterion of H-WDM EDFA is to keep the differential channel output power among digital channels at ≤0.2 dB while providing a high saturated output power of ≥60 mW and a low noise figure of ≤4 dB for the analog channel. A total of nine EDFA configurations are examined and compared in this work, including the dual-forward, dual-backward, and different bidirectional pumping schemes, each with and without the midway optical isolator. The investigation provides the optimum EDFA configuration to design both power and in-line amplifiers for hybrid analog/digital WDM lightwave systems. Such H-WDM technology allows direct transmission of AM-VSB/QAM video traffic from the fiber backbone supertrunking networks to the hybrid-fiber-coaxial (HFC), fiber-to-the-curb (FTTC), or fiber-to-the-home (FTTH) broadband access networks without the complicated and costly signal format conversion at the CATV head-end and hubs.

Low-Distortion and High-Output Optical Power Amplifier for Analog Transmission Employing Hybrid Erbium-Doped Fiber Configuration

We have proposed a novel configuration of erbium-doped fiber amplifier (EDFA) which realizes both a flat spectral gain and high output power for analog transmission. This EDFA uses hybrid EDF which consists of serially cascaded EDFs with different glass compositions, based on the fact that EDFs with certain glass compositions exhibit gain tilt of opposite signs in the wavelength range of interest. It is theoretically shown that, in the hybrid EDFA, the gain flattening under any required optical input/output conditions is possible without sacrificing output power by optimizing the constituent EDF lengths. By using thus designed hybrid EDFAs, 50-channel amplitude-modulated vestigial-sideband signals were successfully amplified in four stages with no significant degradation of signal distortions.