Article
Optics
Shuangxi Zhang, Jianfei Liu, Xiangye Zeng, Jia Lu, Ying Wei, Ruiming Qi
Summary: A modified partitioned frequency domain equalization algorithm is proposed in this paper to address the slow convergence speed and poor equalization effect of digital equalizer in the polarization division multiplexed (PDM)-MDM system. Simulation results show that the modified algorithm can achieve significantly better SER performance and improve the convergence rate compared to the traditional algorithm.
Article
Engineering, Electrical & Electronic
Masato Yoshida, Takashi Kan, Keisuke Kasai, Toshihiko Hirooka, Masataka Nakazawa
Summary: The demonstration showcased a secure physical layer transmission at 10 Tbit/s achieved through digital coherent QAM quantum noise stream cipher (QNSC) and injection-locked WDM techniques. The use of an FPGA-based transmitter and receiver allowed for online transmission over 160 km with high spectral efficiency and enhanced security features.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Mingqing Zuo, Jiaxin Liu, Gang Qiao, Lei Shen, Yuyang Gao, Dawei Ge, Yongqi He, Zhangyuan Chen, Juhao Li
Summary: In this paper, an effective method for monitoring intra-LP-mode dispersion in weakly-coupled mode-division multiplexing (MDM) systems is proposed and experimentally validated in few-mode fiber. The influences of chromatic dispersion, optical signal to noise ratio, and inter-LP-mode crosstalk to the method are also investigated.
IEEE PHOTONICS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Yingjuan Ci, Fang Ren, Xiao Lei, Yanfei Zhang, Xiaohui Wang, Jianping Wang
Summary: We propose a weakly-coupled air-hole-bow-tie-assisted few-mode fiber (AH-BT-FMF) that supports 26 eigenmodes across the C + L band for short-haul communication systems. By introducing an elliptical core, air holes, and a bow-tie stress-applying area, we effectively split adjacent eigenmodes. We evaluate the fiber's parameters and investigate its broadband performance, including the effective refractive index difference, differential mode delay, dispersion, and effective area.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Optics
Bhagyalaxmi Behera, Shailendra Kumar Varshney, Mihir Narayan Mohanty
Summary: This work presents a new fiber design that can support ten modes with large mode separation and low optical loss in the C-band. The fiber design optimizes the chromatic dispersion parameter and bending loss and meets the ITU-G.655 standard.
Article
Optics
Rafal Kasztelanic, Damian Michalik, Alicja Anuszkiewicz, Ryszard Buczynski
Summary: The objective of this study is to optimize the optical fiber structure for mode-division multiplexing systems using nanostructurization. Three optimization schemes have been proposed to design fibers with excellent optical properties. The research findings show a high effective refractive index difference between linearly polarized few-mode fibers while maintaining other important parameters.
Article
Engineering, Electrical & Electronic
Hao Guo, Ting Li, Fengping Yan, Guobin Ren, Wei Wang, Xiangdong Wang, Qi Qin, Guifang Wu, Jiao Gao, Baoyuan Wang, Haoyu Tan, Wenhua Ren, Ting Feng
Summary: This article reports the design and characterization of a six-mode erbium-doped fiber amplifier (6M-EDFA) for mode division multiplexing systems. The design utilizes a center-depressed optical fiber and adjustment of parameters to reduce splice loss. Through analysis and optimization, high gain and low differential modal gain are achieved. The performance of the designed amplifier is verified using a MDM transmission system.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Jianbo Zhang, Xiong Wu, Jianping Li, Linyue Lu, Jiajing Tu, Zhaohui Li, Chao Lu
Summary: Vector modes, as the eigenmodes of optical fiber, have potential for high-capacity spatial division multiplexing and mode division multiplexing. Experimental demonstrations show various high-capacity signal transmission schemes, highlighting the enormous potential of VMDM technology in optical interconnects.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Shohei Beppu, Masahiro Kikuta, Koji Igarashi, Hiroshi Mukai, Masahiro Shigihara, Yasuo Saito, Daiki Soma, Hidenori Takahashi, Noboru Yoshikane, Takehiro Tsuritani, Itsuro Morita, Masatoshi Suzuki
Summary: In this work, we demonstrate the experimental implementation of real-time transoceanic space-division multiplexed transmission using coupled-core multicore fibers. By employing real-time multiple-input multiple-output (MIMO) digital signal processing based on field programmable gate array circuits, we successfully demonstrate 16-channel wavelength-division multiplexed coupled four-core fiber transmission over a distance of 7200 km. These results show the feasibility of real-time coupled-core multicore fiber transmission.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Jinglong Zhu, Yu Yang, Mingqing Zuo, Qichen He, Dawei Ge, Zhangyuan Chen, Yongqi He, Juhao Li
Summary: In this paper, a novel FM-GFF based on LPFG in DC-FMF is proposed to achieve independent gain flattening for each core mode. The weakly-coupled connection between DC-FMF and transmission FMF is maintained by their shared characteristics. Simulation results show that the proposed scheme can flatten the output gain spectra for all core modes in the DC-FMF to less than 0.6 dB in the entire C-band.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Anirudh Vijay, Joseph M. Kahn
Summary: Direct-detection links using mode division multiplexing (MDM) in multimode fiber (MMF) can compensate for crosstalk by employing receiver-side optical signal processing (OSP), and to enable MDM in higher-order mode groups, transmitter-side OSP is proposed. However, modal dispersion and higher-order modal dispersion (MD) limit the performance of OSP in mitigating inter-symbol interference and crosstalk. The impact of higher-order MD can be predicted by the PM coherence bandwidth or the group-delay spread within a mode group.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Sihan Wang, Ran Gao, Xiangjun Xin, Sitong Zhou, Huan Chang, Zhipei Li, Fu Wang, Dong Guo, Chao Yu, Xinyu Liu, Ze Dong, Han Zhang, Fei Wang
Summary: In this article, a novel Bayes-Adam-based MIMO equalizer was proposed and experimentally demonstrated for an OAM-MDM optical fiber communication system. The MIMO equalizer successfully compensates for the crosstalk caused by random intra-group mode coupling. By smoothing the cost function, the proposed equalizer achieves global optimization with fast convergence and high accuracy.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Hanzi Huang, Haoshuo Chen, Yetian Huang, Qianwu Zhang, Jian Chen, Nicolas K. Fontaine, Mikael Mazur, Roland Ryf, Yingxiong Song
Summary: This research investigates the beat interference caused by the spatial coupling between a pilot-tone and signals in self-homodyne coherent transmission. Conventional MIMO and UPIC-assisted MIMO are both affected by the beat interference and additional loss introduced by PT-signal crosstalk. Two novel MIMO processing schemes are proposed to handle the beat interference and show performance improvement in simulations and experiments.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Jiwei Zhang, Guorui Wang, Han Zhang, Fang Wang, Xin Yan, Xuenan Zhang, Shuguang Li, Tonglei Cheng
Summary: This paper proposes a novel refractive index profile design based on few-mode fibers to support 4 linear polarization modes. By using the finite element method, the parameters of NH-HIR and GC-HIR optical fibers are adjusted to investigate their minimum effective refractive index difference, with GC-HIR fiber showing better performance in crosstalk suppression. The proposed GC-HIR FMF has potential applications in MDM optical fiber communication systems and provides a theoretical foundation for the design and analysis of subsequent optical fibers and key components.
IEEE PHOTONICS JOURNAL
(2021)
Article
Optics
Pavel S. Anisimov, Evgeny D. Tsyplakov, Viacheslav V. Zemlyakov, Jiexing Gao
Summary: We present an alternative method for compensating intermodal interactions in few-mode optical fibers using digital backpropagation. Instead of solving the inverse generalized multimode nonlinear Schrodinger equation, we utilize a deep neural network to backpropagate multimode signals based on their near-field intensity distributions captured by a camera. We demonstrate the feasibility of this approach by training an autoencoder for backpropagation of six linearly polarized modes in a step-index fiber.
CHINESE OPTICS LETTERS
(2023)
Article
Computer Science, Hardware & Architecture
R. Munoz, N. Yoshikane, R. Vilalta, J. M. Fabrega, L. Rodriguez, R. Casellas, M. Svaluto Moreolo, R. Martinez, L. Nadal, D. Soma, Y. Wakayama, S. Beppu, S. Sumita, T. Tsuritani, I. Morita
JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING
(2019)
Article
Computer Science, Hardware & Architecture
R. Munoz, N. Yoshikane, R. Vilalta, J. M. Fabrega, L. Rodriguez, D. Soma, S. Beppu, S. Sumita, R. Casellas, R. Martinez, T. Tsuritani, I. Morita
JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING
(2020)
Article
Engineering, Electrical & Electronic
Shohei Beppu, Daiki Soma, Seiya Sumita, Yuta Wakayama, Hidenori Takahashi, Takehiro Tsuritani, Itsuro Morita, Masatoshi Suzuki
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2020)
Article
Computer Science, Hardware & Architecture
C. Manso, R. Munoz, N. Yoshikane, R. Casellas, R. Vilalta, R. Martinez, T. Tsuritani, I Morita
Summary: Network operators are tackling the challenge of increasing network capacity by a factor of 10 while maintaining cost efficiency, with optical disaggregation and SDM being considered key technologies to achieve this goal.
JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING
(2021)
Article
Computer Science, Hardware & Architecture
Ricard Vilalta, Carlos Manso, Noboru Yoshikane, Ramon Casellas, Ricardo Martinez, Takehiro Tsuritani, Itsuro Morita, Raul Munoz
Summary: This paper presents an experimental evaluation of network protocols for control and management of optical networks and equipment. It introduces YANG data modeling language, multiple data models, telemetry protocols, and a zero-touch SDN controller architecture. The protocol implementations are experimentally evaluated and integration recommendations are provided.
JOURNAL OF OPTICAL COMMUNICATIONS AND NETWORKING
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Raul Munoz, Noboru Yoshikane, Ricard Vilalta, Ramon Casellas, Ricardo Martinez, Takehiro Tsuritani, Itsuro Morita
2020 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
S. Beppu, K. Igarashi, H. Mukai, M. Kikuta, M. Shigihara, D. Soma, T. Tsuritani, I Morita
2020 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXPOSITION (OFC)
(2020)
Proceedings Paper
Computer Science, Information Systems
Daiki Soma, Shohei Beppu, Hidenori Takahashi, Noboru Yoshikane, Itsuro Morita, Takehiro Tsuritani
2020 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATIONS (ECOC)
(2020)
Proceedings Paper
Computer Science, Information Systems
R. Vilalta, C. Manso, N. Yoshikane, R. Munoz, R. Casellas, R. Martinez, T. Tsuritani, I Morita
2020 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATIONS (ECOC)
(2020)
Proceedings Paper
Computer Science, Information Systems
R. Vilalta, N. Yoshikane, R. Casellas, R. Martinez, T. Tsuritani, I Morita, R. Munoz
2020 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATIONS (ECOC)
(2020)
Proceedings Paper
Computer Science, Information Systems
Shohei Beppu, Daiki Soma, Hidenori Takahashi, Noboru Yoshikane, Itsuro Morita, Takehiro Tsuritani
2020 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATIONS (ECOC)
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
Masatoshi Suzuki, Daiki Soma, Takehiro Tsuritani, Itsuro Morita
2020 22ND INTERNATIONAL CONFERENCE ON TRANSPARENT OPTICAL NETWORKS (ICTON 2020)
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
R. Munoz, N. Yoshikane, J. M. Fabrega, L. Rodriguez, R. Vilalta, D. Soma, S. Beppu, S. Sumita, R. Casellas, R. Martinez, T. Tsuritani, I. Morita
2019 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC)
(2019)
Proceedings Paper
Engineering, Electrical & Electronic
Takehiro Tsuritani, Daiki Soma, Yuta Wakayama, Yuichi Miyagawa, Mikoto Takahashi, Itsuro Morita, Koichi Maeda, Kohei Kawasaki, Toshikazu Matsuura, Masatoshi Tsukamoto, Ryuichi Sugizaki
2019 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION (OFC)
(2019)
