Article
Engineering, Electrical & Electronic
Adolfo V. T. Cartaxo, Jose A. P. Morgado
Summary: A closed-form expression is proposed for evaluating mean inter-core crosstalk (ICXT) power in weakly-coupled multi-core fibers, showing improved accuracy compared to the existing expression by Koshiba. The proposed expression predicts a significant influence of the twisting period on the mean ICXT power, in qualitative agreement with experimental results reported by other authors.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Fengxian Tang, Gangxiang Shen, George N. Rouskas
Summary: This article discusses the design of MCF-EONs with shared-backup path protection (SBPP) to minimize inter-core crosstalk and network spectrum resources. The problem is formulated as an integer linear programming (ILP) model with strict inter-core crosstalk limits for each lightpath, and an auxiliary graph (AG) based heuristic algorithm is proposed for lightpath provisioning. Simulation studies show the effectiveness and efficiency of the algorithm, especially in small networks where solving the ILP is feasible.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Bruno R. P. Pinheiro, Joao L. Rebola, Adolfo V. T. Cartaxo
Summary: The influence of inter-core crosstalk (ICXT) on the performance of weakly-coupled multi-core fiber systems with coherent detection was studied. The study showed that with increasing skew-symbol rate product, system stability and maximum allowable ICXT level also increased, aligning with the results of other experiments.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Adolfo V. T. Cartaxo
Summary: This study investigates the impact of core loss imbalance on inter-core crosstalk in long-haul bidirectional uncoupled multi-core fiber transmission. The research shows that within a certain range, the loss coefficient imbalance has a linear effect on the crosstalk powers, with significant differences observed for different levels of imbalance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Qihan Zhang, Xu Zhang, Xiaoxue Gong, Lei Guo
Summary: This paper discusses the challenges that high-bandwidth services bring to optical networks in the era of 5th generation fixed networks and proposes a solution using virtual optical network embedding (VONE) over heterogeneous multi-core fiber (HMCF) structures to address the problem of inter-core crosstalk (IC-XT). The paper establishes integer linear programming (ILP) models and presents a novel algorithm to support joint IC-XT-avoid cores and frequency slots assignment. Simulation results demonstrate the effectiveness of the proposed algorithm in improving the available frequency ratio (AFR) and reducing the fragmentation ratio (FR).
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Lian Xiang, Shulin Jin, Weidong Shao, Mingyi Gao
Summary: A split-step coupling method is introduced to solve the nonlinear coupled mode equation (NCME) and a split-step numerical model (SNM) is proposed for evaluating inter-core crosstalk in the nonlinear regime. The SNM treats linear coupling and fiber nonlinear effect as two independent operators in the transmission of optical signals. Experiments and simulations are conducted on a 10 km 7-core fiber, showing that a significant crosstalk suppression can be achieved with high launch power in the nonlinear region. Compared to traditional linear models, the SNM proves to be more accurate in evaluating inter-core crosstalk.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Alexis Carbo Meseguer, Juliana Tiburcio de Araujo, Jean-Christophe Antona
Summary: This article studies the technical viability of Multi-core and Hollow-core fibers for submarine links, taking into account transceiver limitations and typical power constraints. The opportunities and challenges of adopting these technologies in the mid and long-term are discussed. Results show that Hollow-core fibers are not yet competitive with multi-core fibers, but may be in certain power-constrained scenarios. Coupled-core fibers and Hollow-core fibers with higher potential bandwidth are considered for long-term scenarios, but power limitations and fiber attenuation must be addressed to achieve higher capacities.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Georg Rademacher, Ruben S. Luis, Benjamin J. Puttnam, Roland Ryf, Sjoerd van der Heide, Tobias A. Eriksson, Nicolas K. Fontaine, Haoshuo Chen, Rene-Jean Essiambre, Yoshinari Awaji, Hideaki Furukawa, Naoya Wada
Summary: The study explores high-capacity, long-haul transmission over a coupled-core three-core multi-core fiber through experiments. Key system characteristics, optimum launch power, wavelength dependence, and distance-evolution of mode-dependent loss were reported. High data-rate transmission demonstrations with over 75 nm optical bandwidth were achieved, showcasing the potential of using coupled-core multi-core fibers for wideband optical signals over long distances.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Xiaofan Ji, Yaping Liu, Honglin Sun, Wenbo Yu, Zhiqun Yang, Lin Zhang
Summary: In this paper, we study the scaling of nonlinear impairment in coupled-core multi-core fibers (CC-MCFs) with different core counts. The results show that increasing the number of cores in CC-MCFs significantly weakens the nonlinear signal degradation, which is of great interest for ultralong-haul transmission. We further analyze the impact of fiber loss, differential group delay, and effective mode field area on this trend. Moreover, we compare CC-MCFs with few-mode fibers with the same number of spatial modes and find that CC-MCFs tend to have better nonlinear performance. It is also shown that few-mode fibers operated in a strong coupling regime are promising for long-haul transmission.
OPTICS COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Lin Sun, Gordon Ning Liu, Yi Cai, Jiangbing Du, Zuyuan He, Zhaohui Li, Chao Lu, Gangxiang Shen
Summary: This study proposes the use of orthogonal filtering technique to suppress inter-core crosstalk in multicore fiber transmission. By extracting individual channels separately, the implementation of signal reception can be simplified without the need for multiple-input and multiple-output digital signal processing.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Tetsuya Hayashi, Taiji Sakamoto, Yusuke Yamada, Roland Ryf, Rene-Jean Essiambre, Nicolas Fontaine, Mikael Mazur, Haoshuo Chen, Takemi Hasegawa
Summary: Randomly-coupled multi-core fiber (MCF) technology has gained attention for its applicability in long-haul transmission systems. Compared to weakly-coupled MCFs, randomly-coupled MCFs can achieve higher spatial channel density and lower transmission loss using existing single-mode fiber core designs. This article provides an overview of the advancements in randomly-coupled MCF technology, including its classification, design, optical property characterization methods, and performance improvements in transmissions.
PROCEEDINGS OF THE IEEE
(2022)
Article
Optics
T. W. Kelly, P. Horak, I. A. Davidson, M. Partridge, G. T. Jasion, S. Rikimi, A. Taranta, D. J. Richardson, F. Poletti, N. Wheeler
Summary: Hollow-core fibers (HCFs) with glass membranes defining a hollow core can have their optical properties dramatically changed, including loss, bend loss, and modality, by introducing an extremely small gas-induced differential refractive index (GDRI). This provides a new means to control the optical properties of HCF post-fabrication, enhance their performance, and open up new design possibilities.
Article
Optics
Yanbo Chen, Nan Feng, Yue Zhou, Danping Ren, Jijun Zhao
Summary: This paper focuses on maximizing spectral resource utilization while satisfying cross-talk (XT) constraints in Space Division Multiplexing Elastic Optical Networks (SDM-EONs) based on Multi-Core Fiber (MCF) technologies. Firstly, a three-dimensional metric model is optimized to evaluate XT and fragmentation more accurately. Secondly, a cross-talk classification (CC) algorithm is proposed to adjust the XT constraints according to the network's actual situation. Moreover, a synthetically consider cross-talk and fragmentation (SCCF) algorithm is proposed to match the CC algorithm, which describes the cross-talk and fragmentation in the network.
Article
Optics
Yulin Sheng, Yizhi Sun, Shoufei Gao, Zhi Liang, Yifeng Hong, Yingying Wang, Wei Ding
Summary: Precise control of group velocity dispersion (GVD) in gas-filled hollow-core fibers (HCF) is crucial for gas-based nonlinear optical applications. An analytical model, combining the contributions of the gas material, capillary waveguide, and cladding resonances, accurately calculates pressure-induced dispersion variations. Experimental measurements validate the model and show a pronounced negative dispersion for the first time.
Article
Optics
Afzal Hossain, S. P. Majumder
Summary: The study found that crosstalk in 9-core and 7-core multi-core optical fibers is more pronounced compared to the 3-core fiber, leading to significant deterioration in Bit Error Rate (BER) performance. Additionally, there is a minimum achievable BER corresponding to specific core pitch and number.
Article
Engineering, Electrical & Electronic
Sjoerd van der Heide, Ruben S. Luis, Benjamin J. Puttnam, Georg Rademacher, Ton Koonen, Satoshi Shinada, Yohinari Awaji, Hideaki Furukawa, Chigo Okonkwo
Summary: This article presents a flexible, software-defined real-time multi-modulation format receiver implemented on a general-purpose graphics processing unit (GPU), capable of processing various modulation signals. Performance evaluation was conducted through experiments and testing on a high-speed research and development network.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Sjoerd van Der Heide, Ruben S. Luis, Benjamin J. Puttnam, Georg Rademacher, Ton Koonen, Satoshi Shinada, Yohinari Awaji, Hideaki Furukawa, Chigo Okonkwo
Summary: Real-time transmission over a 10,000 km straight-line link is achieved using a software-defined multi-modulation format receiver. Various QAM signals are successfully transmitted over different distances.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Georg Rademacher, Ruben S. Luis, Benjamin J. Puttnam, Roland Ryf, Sjoerd van der Heide, Tobias A. Eriksson, Nicolas K. Fontaine, Haoshuo Chen, Rene-Jean Essiambre, Yoshinari Awaji, Hideaki Furukawa
Summary: This paper compares the use of 3-mode few-mode fibers and 3-core coupled-core multi-core fibers in space-division multiplexed transmission systems. The analysis shows that the coupled-core multi-core fiber achieves higher data rates at shorter transmission distances.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Benjamin J. Puttnam, Ruben S. Luis, Georg Rademacher, Manuel Mendez-Astudillio, Yoshinari Awaji, Hideaki Furukawa
Summary: This study investigates the optical transmission of an ultra-wideband signal in a standard single mode fiber. By utilizing a near continuous optical bandwidth and combining doped-fiber amplifiers and distributed Raman amplification, high-quality transmission of polarization division multiplexed (PDM)-256-quadrature-amplitude modulation (QAM) signals over a standard single-mode fiber is achieved.
Article
Optics
Ruben S. Luis, Benjamin J. Puttnam, Georg Rademacher, Yoshinari Awaji, Hideaki Furukawa
Summary: This work demonstrates the use of bidirectional Raman amplification to achieve a long-distance optical link without repeaters. It achieves a high capacityxdistance product and a throughput above 90 Tb/s by utilizing wavelength-division multiplexing and high-speed transmission signals.
Article
Optics
Sjoerd van der Heide, Ruben S. Luis, Sebastiaan Goossens, Benjamin J. Puttnam, Georg Rademacher, Ton Koonen, Satoshi Shinada, Yoshinari Awaji, Alex Alvarado, Hideaki Furukawa, Chigo Okonkwo
Summary: A software-defined optical receiver implemented on a commercial graphics processing unit (GPU) is capable of processing various orders of quadrature amplitude modulation (QAM) signals, and its performance is validated over a 91 km fiber link.
Article
Optics
Ilaria Cristiani, Cosimo Lacava, Georg Rademacher, Benjamin J. Puttnam, Ruben S. Luis, Cristian Antonelli, Antonio Mecozzi, Mark Shtaif, Daniele Cozzolino, Davide Bacco, Leif K. Oxenlowe, Jian Wang, Yongmin Jung, David J. Richardson, Siddharth Ramachandran, Massimiliano Guasoni, Katarzyna Krupa, Denis Kharenko, Alessandro Tonello, Stefan Wabnitz, David B. Phillips, Daniele Faccio, Tijmen G. Euser, Shangran Xie, Philip St J. Russell, Daoxin Dai, Yu Yu, Periklis Petropoulos, Frederic Gardes, Francesca Parmigiani
Summary: Multimode devices and components have garnered significant attention in recent years, opening up new possibilities for designing more complex and sophisticated optical components. By utilizing different modes of propagation, these devices can increase fiber optic capacity, introduce novel intermodal interactions, and allow for complex manipulation of optical modes to cater to various applications.
Proceedings Paper
Engineering, Electrical & Electronic
Georg Rademacher, Ruben S. Luis, Benjamin J. Puttnam, Juan Carlos Alvarado Zacarias, Rodrigo Amezcua-Correa, Kazuhiko Aikawa, Yoshinari Awaji, Hideaki Furukawa
Summary: We experimentally investigated the utilization of distributed Raman amplification in a graded-index three-mode fiber, achieving a signal bandwidth of over 80 nm. By pumping only the highest-order modes, we measured a gain of up to 6 dB with a mode-dependence of 0.3 dB.
2022 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
A. Gatto, M. Rapisarda, P. Parolari, B. J. Puttnam, G. Rademacher, R. S. Luis, P. Boffi
Summary: The study explores the impact of inter-core crosstalk on DMT-modulated signals in a 7-core fiber with different sources at the same nominal wavelength. It is observed that beating from relative laser frequency shift leads to time-dependent interference on DMT subcarriers.
2021 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
(2021)
Proceedings Paper
Computer Science, Information Systems
Ruben S. Luis, Benjamin J. Puttnam, Georg Rademacher, Yoshinari Awaji, Hideaki Furukawa
Summary: The study reveals a delay dependence of 40ps/km/degrees C for the impulse response of a multi-core fiber, while showing negligible variation in the duration with temperature changes.
2021 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION (ECOC)
(2021)
Proceedings Paper
Computer Science, Information Systems
Georg Rademacher, Benjamin J. Puttnam, Ruben S. Luis, Tobias A. Eriksson, Nicolas K. Fontaine, Mikael Mazur, Haoshuo Chen, Roland Ryf, David T. Neilson, Pierre Sillard, Frank Achten, Yoshinari Awaji, Hideaki Furukawa
Summary: Space-division multiplexing (SDM) allows for the transmission of independent data channels over different fiber modes of multi-mode fibers, achieving high-speed transmission. One recent notable demonstration of SDM transmission is the achievement of 1.01 peta-bit/s transmission in a 15-mode fiber.
2021 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION (ECOC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Benjamin J. Puttnam, Ruben S. Luis, Georg Rademacher, Manuel Mendez-Astudilio Yoshinari Awaji, Hideaki Furukawa
Summary: This technology utilizes Erbium and Thulium doped-fiber amplifiers with distributed Raman amplification to transmit a high amount of channels over standard single-mode fiber, achieving a data rate of 206.1 Tb/s.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Georg Rademacher, Ruben S. Luis, Benjamin J. Puttnam, Roland Ryf, Sjoerd van der Heide, Tobias A. Eriksson, Nicolas K. Fontaine, Haoshuo Chen, Rene-Jean Essiambre, Yoshinari Awaji, Hideaki Furukawa
Summary: The text discusses recent wideband, high-capacity transmission experiments using either few-mode or coupled-core multi-core fibers. It highlights that the coupled-core multi-core fiber has overall favorable transmission properties at the cost of a lower spatial channel density.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Sjoerd van der Heide, Ruben S. Luis, Benjamin J. Puttnam, Georg Rademacher, Ton Koonen, Satoshi Shinada, Yohinari Awaji, Hideaki Furukawa, Chigo Okonkwo
Summary: This paper demonstrates real-time operation of a software-defined, GPU-based optical receiver over a 100-span straight-line optical link, and evaluates the performance of minimum-phase Kramers-Kronig 4-, 8-, 16-, 32-, and 64-QAM signals at various distances.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
F. Da Ros, U. C. de Moura, R. S. Luis, G. Rademacher, B. J. Puttnam, A. M. Rosa Brusin, A. Carena, Y. Awaji, H. Furukawa, D. Zibar
Summary: Experimentally-trained neural network models are used to optimize the 12 Raman pumps of a C+L band hybrid EDFA-Raman amplifier, achieving decreased gain ripples from 6.7 to 1.9 dB.
2021 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2021)
