Fast-Convergence Digital Signal Processing for Coherent PON Using Digital SCM

Journal of Lightwave Technology, Год журнала: 2023, Номер 41(14), С. 4635 - 4643

Опубликована: Фев. 10, 2023

It is foreseeable that the 100 Gb/s/ $\lambda$ and beyond passive optical network (PON) will be required in future access networks to meet explosive growth of data traffic. The coherent systems could a promising solution for G PON. Coherent PON using digital subcarrier multiplexing (DSCM) can provide flexible bandwidth allocation large number subscribers by dividing subcarriers DSCM signal into time slots time-and-frequency division multiple access. When unit allocated new subcarrier, processing (DSP) should converge fast slot ensure low handoff latency real-time allocation. However, traditional DSP hard realize convergence due blind complex algorithms. In this paper, we design specific training sequence (TS) structure propose data-aided achieve feasibility proposed scheme experimentally verified an 8 Gbaud/SC×8 SCs 400 Gb/s-net-rate with 16 quadrature amplitude modulation. experimental results show jointly realized TS 416-symbol 52 ns duration. receiver sensitivity at 20% soft-decision forward error correction limit approximately notation="LaTeX">$\mathbf{-27}$ dBm power budget about 35.5 dB achieved booster amplifier.

Язык: Английский

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Flexible Coherent Optical Access: Architectures, Algorithms, and Demonstrations

Journal of Lightwave Technology, Год журнала: 2024, Номер 42(4), С. 1193 - 1202

Опубликована: Янв. 18, 2024

To cope with the explosive bandwidth demand, significant progress has been made in ITU-T standardization sector to define a higher-speed passive optical network (PON) 50 Gb/s line rate. Recently, G PON become mature gradually, which means it is time discuss beyond PON. For ensuring an acceptable power budget, will potentially use coherent technologies, can simultaneously promote applications of flexible multiple access such as time/frequency-domain (TFDMA). In this paper, we introduce architectures, algorithms, and demonstrations for TFDMA-based The system architectures based on ultra-simple transceiver specific signal spectra are designed reduce cost ONUs greatly. Meanwhile, continuous-mode burst-mode digital processing (DSP) algorithms proposed dealing downstream upstream signals, respectively. Based experimentally demonstrate first real-time where Gb/(s × subcarrier) continuous 12.5 burst processed real time. Owing independent subcarrier processing, potential support peak rates 200 (i.e. four subcarriers) 100 eight subcarriers). Significantly, have sufficiently verified by demonstrations. conclusion, technologies make more possible be applied future

Язык: Английский

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End-to-End Optimization of Constellation Shaping for Wiener Phase Noise Channels With a Differentiable Blind Phase Search

Journal of Lightwave Technology, Год журнала: 2023, Номер 41(12), С. 3849 - 3859

Опубликована: Апрель 6, 2023

As the demand for higher data throughput in coherent optical communication systems increases, we need to find ways increase capacity existing and future links. To address spectral efficiencies, apply end-to-end optimization joint geometric probabilistic constellation shaping presence of Wiener phase noise carrier estimation. Our approach follows state-of-the-art bitwise auto-encoders, which require a differentiable implementation all operations between transmitter receiver, including DSP algorithms. In this work, show how modify ubiquitous blind search (BPS) algorithm, popular estimation make it include shaping. By leveraging shaping, are able obtain robust pilot-free modulation scheme improving performance 64-ary by at least 0.1bit/symbol compared square QAM constellations with neural demappers 0.05 bit/symbol previously presented approaches applying only

Язык: Английский

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Formation of methodological approaches to increasing the efficiency of optical networks

E3S Web of Conferences, Год журнала: 2024, Номер 474, С. 02009 - 02009

Опубликована: Янв. 1, 2024

In modern conditions of organizing the work IT infrastructure, issue increasing efficiency optical network is relevant and in demand. this regard, to formalize methodological approaches argue theoretical prerequisites for networks, an in-depth analysis main methods directions was carried out. The advantages using method transforming architecture topology are argued. types networks stated: passive, hybrid, elastic, followed by highlighting key technologies identifying promising options efficiency. Optimization opportunities highlighted operation PoF cable super coherent technologies. Aspects a software solution improve touched upon. use redundancy justified as one network. Methodological have been formed can be applied practice when information results study.

Язык: Английский

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The “X-Factor” of 6G Networks: Optical Transport Empowering 6G Innovations

IT Professional, Год журнала: 2024, Номер 26(1), С. 32 - 39

Опубликована: Янв. 1, 2024

The sixth generation (6G) of mobile networks will radically change the way that we interact, as artificial intelligence (AI)-enabled fixed and wireless communications infrastructure offer improved performance an unprecedented variety applications. 6G builds upon evolution 5G, which already introduces various innovations in network architecture, technologies, operation capabilities. We expect further progress across many areas, including evolving Internet Protocol/optical transport (called x-haul) connecting radio access (RAN), core (CN) Internet. It is one on rely upon, it carries aggregated traffic all users circulates world. In this article, address possible innovations, such implementation flexible functional splits end-to-end slicing, from viewpoint evolved x-haul are based novel energy-efficient optical systems technologies.

Язык: Английский

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Scalable filterless coherent point-to-multipoint metro network architecture

Journal of Optical Communications and Networking, Год журнала: 2023, Номер 15(5), С. B53 - B53

Опубликована: Март 24, 2023

Metro aggregation is one of the fastest growing segments in telecommunications terms data traffic. At intersection core and access, where coherent modules compete with direct detection technology, high capacity must be provided at low cost power, enhanced scalability flexibility. Real-life Telecom Italia Mobile metro networks are examined their design planning optimized. The analysis supported by techno-economics, which compares two solutions: traditional point-to-point (P2P) digital subcarrier (DSC)-based for P2P point-to-multipoint transmission. We demonstrate that greater flexibility DSC-based leads to significant savings over a three-phase network deployment.

Язык: Английский

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Improving Equipment Maintenance—Switching from Corrective to Preventative Maintenance Strategies

Buildings, Год журнала: 2024, Номер 14(11), С. 3581 - 3581

Опубликована: Ноя. 11, 2024

This paper explores different building maintenance strategies in commercial buildings Sydney, Australia, focusing on corrective (CM) and preventive (PM). While CM involves rectifying issues after they occur, PM aims to enhance productivity by anticipating potential issues. Although seems more logical, the decision implement this type of strategy are typically made based item reliability, failure frequency, downtime cost, commonly found manufacturing facilities or critical environments. However, as selected/surveyed real estate buildings, was frequently adopted aged with older infrastructure, favoured for without structural deficiencies; however, operating equipment failures were common. many cases, makers did not consider broader effects beyond direct financial losses, costs associated customer satisfaction, worker efficiency, rent abatements, reputation damage. each is unique may require a bespoke schedule, study’s insights help managers select most appropriate strategy. Nonetheless, further research needed investigate role innovative technologies (such machine learning artificial intelligence) enhancing efficacy explore influences economic shifts, corporate objectives, availability technical resources.

Язык: Английский

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Low complexity neural network equalizer for nonlinear mitigation in digital subcarrier multiplexing systems

Optics Express, Год журнала: 2025, Номер 33(2), С. 2558 - 2558

Опубликована: Янв. 8, 2025

This article conducts a comparative study of the complexity reduction neural network (NN) models for nonlinearity compensation used in digital subcarrier multiplexing (DSCM)-based optical communication systems. We employ NN model based on bi-directional long short-term memory (biLSTM) and 1D-convolutional (1D-CNN) layers. To reduce computation proposed solution, weight clustering is applied to NN. specifically compare performance our NN-based equalizer with traditional methods such as chromatic dispersion (CDC), back-propagation (DBP) alternative NN, triplet coefficients perturbation analysis, previous literature, evaluating both Q-factor computational complexity. Our findings show that offers competitive improvements while significantly reducing complexity, particularly when used. can be reduced by up 91.1% compared analysis literature 31.5% DBP 1 step per span. The results underscore potential approaches deliver high-performance nonlinear lower demands, positioning them promising solution future equalizers.

Язык: Английский

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Experimental Assessments of a Coherent DSCM and SOA-based WDM Metro-access Network Architecture with Enhanced Flexibility and Capacity

Optics Letters, Год журнала: 2025, Номер 50(4), С. 1325 - 1325

Опубликована: Янв. 17, 2025

Metro-access networks are a type of optical network connecting metro hubs with various subnetworks, covering from rural to dense urban regions. In the long term, metro-access is expected address hundreds Tb/s aggregated traffic, which makes spectral efficient multiplexing techniques must-have. Combining wavelength division (WDM) and digital subcarrier (DSCM) possible successful industrial approach cope this challenge. However, ever-growing demand for bandwidth/wavelength inevitably induces increased complexity cost architecture. Letter, we describe design experimental assessment semiconductor amplifier (SOA)-based add–drop multiplexer (OADM) coherent DSCM technique, can dynamically add drop traffic at any node within enable lossless transmission relatively low due photonic integration. The results show that proposed architecture support up five nodes net data rate 291 Gb/s/ λ negligible penalty dropping adding operations, indicating its great potential long-term adoption.

Язык: Английский

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Improved Performances in Point-to-Multipoint Flexible Optical Transceivers Utilizing Cascaded Discrete Fourier Transform-Spread Inverse Fast Fourier Transform/Fast Fourier Transform-Based Multi-Channel Aggregation/De-Aggregation

Photonics, Год журнала: 2025, Номер 12(2), С. 106 - 106

Опубликована: Янв. 24, 2025

The previously proposed cascaded inverse fast Fourier transform/fast transform (IFFT/FFT)-based point-to-multipoint (P2MP) flexible optical transceivers have the potential to equip future intensity modulation and direct detection (IMDD) access networks with excellent flexibility, adaptability, scalability upgradability. However, due their IFFT-based multi-channel aggregations, P2MP suffer high peak-to-average power ratios (PAPRs). To address technical challenge, this paper proposes a novel transceiver, which uses discrete transformation-spread (DFT-Spread) IFFT/FFT-based aggregation/de-aggregation standard signal clipping jointly reduce its PAPRs. upstream performances of are numerically explored in 20 km IMDD passive network (PON). results indicate that transceiver’s PAPRs mainly dominated by size last IFFT operation aggregation, almost independent format channel count. Compared conventional without operations, DFT-Spread can 2.6 dB 3.5 dB, respectively, for final 1024. More significant PAPR reductions achievable when is increased further. As result, compared adopting operations only, transceiver improve receiver sensitivities >1.9 aggregated transmission capacities >14.1%. Such capacity enhancements count become more pronounced longer distances.

Язык: Английский

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