Engineering › Electrical and Electronic Engineering

Optical Network Technologies

Works Count: 92408

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Description

This cluster of papers covers advances in optical fiber communication technologies, including topics such as coherent detection, digital signal processing, nonlinear effects, space-division multiplexing, high-capacity networks, modulation formats, fiber amplifiers, dispersion compensation, and optical performance monitoring.

Keywords

Optical Fiber; Coherent Detection; Digital Signal Processing; Nonlinear Effects; Space-Division Multiplexing; High-Capacity Networks; Modulation Formats; Fiber Amplifiers; Dispersion Compensation; Optical Performance Monitoring

Optical solitons : from fibers to photonic crystals

2003-01-01

Yuri S. Kivshar , Govind P. Agrawal

Rare earth doped fiber lasers and amplifiers

1993-01-01

Michel J. F. Digonnet

Rare earth doped fibre fabrication - techniques and physical properties, Jay R. Simpson optical and electronic properties of rare earth ions in glasses, Wiliam J. Miniscalco devices and configurations for … Rare earth doped fibre fabrication - techniques and physical properties, Jay R. Simpson optical and electronic properties of rare earth ions in glasses, Wiliam J. Miniscalco devices and configurations for fibre laser sources and amplifiers, Paul Urquhart theory of operation of laser fibre devices, Michael J.F. Digonnet Nd3+- and Er3+-doped silica fibre lasers, Michael J.F. Digonnet and E. Snitzer narrow line width and tunable fibre lasers, P.R. Morkel broadband operation of erbium- and neodymium-doped fibre sources, Paul F. Wysocki Q-switched fibre lasers, W.L. Barnes mode-locked fibre lasers, Mark W. Phillips rare earth doped heavy-metal fluoride glass fibres, J.S. Sanghera and I.D. Aggarwal erbium-doped fibre amplifiers - basic physics and characteristics, E. Desurvire applications of fibre amplifiers to telecommunications systems, Noboru Edagawa.

Fiber‐Optic Communication Systems

2021-06-04

Govind P. Agrawal

Preface. 1 Introduction. 1.1 Historical Perspective. 1.2 Basic Concepts. 1.3 Optical Communication Systems. 1.4 Lightwave System Components. Problems. References. 2 Optical Fibers. 2.1 Geometrical-Optics Description. 2.2 Wave Propagation. 2.3 Dispersion … Preface. 1 Introduction. 1.1 Historical Perspective. 1.2 Basic Concepts. 1.3 Optical Communication Systems. 1.4 Lightwave System Components. Problems. References. 2 Optical Fibers. 2.1 Geometrical-Optics Description. 2.2 Wave Propagation. 2.3 Dispersion in Single-Mode Fibers. 2.4 Dispersion-Induced Limitations. 2.5 Fiber Losses. 2.6 Nonlinear Optical Effects. 2.7 Fiber Design and Fabrication. Problems. References. 3 Optical Transmitters. 3.1 Semiconductor Laser Physics. 3.2 Single-Mode Semiconductor Lasers. 3.3 Laser Characteristics. 3.4 Optical Signal Generation. 3.5 Light-Emitting Diodes. 3.6 Transmitter Design. Problems. References. 4 Optical Receivers. 4.1 Basic Concepts. 4.2 Common Photodetectors. 4.3 Receiver Design. 4.4 Receiver Noise. 4.5 Coherent Detection. 4.6 Receiver Sensitivity. 4.7 Sensitivity Degradation. 4.8 Receiver Performance. Problems. References. 5 Lightwave Systems. 5.1 System Architectures. 5.2 Design Guidelines. 5.3 Long-Haul Systems. 5.4 Sources of Power Penalty. 5.5 Forward Error Correction. 5.6 Computer-Aided Design. Problems. References. 6 Multichannel Systems. 6.1 WDM Lightwave Systems. 6.2 WDM Components. 6.3 System Performance Issues. 6.4 Time-Division Multiplexing. 6.5 Subcarrier Multiplexing. 6.6 Code-Division Multiplexing. Problems. References. 7 Loss Management. 7.1 Compensation of Fiber Losses. 7.2 Erbium-Doped Fiber Amplifiers. 7.3 Raman Amplifiers. 7.4 Optical Signal-To-Noise Ratio. 7.5 Electrical Signal-To-Noise Ratio. 7.6 Receiver Sensitivity and Q Factor. 7.7 Role of Dispersive and Nonlinear Effects. 7.8 Periodically Amplified Lightwave Systems. Problems. References. 8 Dispersion Management. 8.1 Dispersion Problem and Its Solution. 8.2 Dispersion-Compensating Fibers. 8.3 Fiber Bragg Gratings. 8.4 Dispersion-Equalizing Filters. 8.5 Optical Phase Conjugation. 8.6 Channels at High Bit Rates. 8.7 Electronic Dispersion Compensation. Problems. References. 9 Control of Nonlinear Effects. 9.1 Impact of Fiber Nonlinearity. 9.2 Solitons in Optical Fibers. 9.3 Dispersion-Managed Solitons. 9.4 Pseudo-linear Lightwave Systems. 9.5 Control of Intrachannel Nonlinear Effects. Problems. References. 10 Advanced Lightwave Systems. 10.1 Advanced Modulation Formats. 10.2 Demodulation Schemes. 10.3 Shot Noise and Bit-Error Rate. 10.4 Sensitivity Degradation Mechanisms. 10.5 Impact of Nonlinear Effects. 10.6 Recent Progress. 10.7 Ultimate Channel Capacity. Problems. References. 11 Optical Signal Processing. 11.1 Nonlinear Techniques and Devices. 11.2 All-Optical Flip-Flops. 11.3 Wavelength Converters. 11.4 Ultrafast Optical Switching. 11.5 Optical Regenerators. Problems. References. A System of Units. B Acronyms. C General Formula for Pulse Broadening. D Software Package.

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Optical Fiber Communications

1991-01-01

Gerd Keiser

Space-division multiplexing in optical fibres

2013-04-29

David J. Richardson , John M. Fini , L.E. Nelson

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All-optical wavelength conversion by semiconductor optical amplifiers

1996-06-01

T. Durhuus , B. Mikkelsen , C. Jœrgensen +2 more

Following a brief introduction to the applications for wavelength conversion and the different available conversion techniques, the paper gives an in depth analysis of cross gain and cross phase wavelength … Following a brief introduction to the applications for wavelength conversion and the different available conversion techniques, the paper gives an in depth analysis of cross gain and cross phase wavelength conversion in semiconductor optical amplifiers. The influence of saturation filtering on the bandwidth of the converters is explained and conditions for conversion at 20 Gb/s or more are identified. The cross gain modulation scheme shows extinction ratio degradation for conversion to longer wavelengths. This can be overcome using cross phase modulation in semiconductor optical amplifiers that are integrated into interferometric structures. The first results for monolithic integrated interferometric wavelength converters are reviewed, and the quality of the converted signals is demonstrated by transmission of 10 Gb/s converted signals over 60 km of nondispersion shifted single mode fiber.

The GN Model of Non-Linear Propagation in Uncompensated Coherent Optical Systems

2012-09-06

P. Poggiolini

This paper is devoted to an in-depth discussion of the Gaussian Noise (GN) model which describes non-linear propagation in uncompensated coherent transmission systems. Similar models and validation efforts are reviewed. … This paper is devoted to an in-depth discussion of the Gaussian Noise (GN) model which describes non-linear propagation in uncompensated coherent transmission systems. Similar models and validation efforts are reviewed. Then, the main equations of the GN model are introduced. An intuitive physical interpretation of the equations and their features is proposed. The main characteristics of the non-linear interference (NLI) noise spectra that the GN model produces are discussed. To ease model exploitation, a new formulation in hyperbolic coordinates is proposed, which makes numerical integration faster. New approximate closed-form solutions are also provided. An extension of the GN model to distributed-amplification scenarios is introduced. NLI noise accumulation versus distance and bandwidth are studied in depth. Finally, the GN model implications as to system and networks design and optimization are discussed.

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The GN-Model of Fiber Non-Linear Propagation and its Applications

2014-01-24

P. Poggiolini , Gabriella Bosco , Andrea Carena +3 more

Several approximate non-linear fiber propagation models have been proposed over the years. Recent re-consideration and extension of earlier modeling efforts has led to the formalization of the so-called Gaussian-noise (GN) … Several approximate non-linear fiber propagation models have been proposed over the years. Recent re-consideration and extension of earlier modeling efforts has led to the formalization of the so-called Gaussian-noise (GN) model. The evidence collected so far hints at the GN-model as being a relatively simple and, at the same time, sufficiently reliable tool for performance prediction of uncompensated coherent systems, characterized by a favorable accuracy versus complexity trade-off. This paper tries to gather the recent results regarding the GN-model definition, understanding, relations versus other models, validation, limitations, closed form solutions, approximations and, in general, its applications and implications in link analysis and optimization, also within a network environment.

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Erbium-Doped Fiber Amplifiers: Principles and Applications

1995-02-01

E. Desurvire , M.N. Zervas

It is now widely recognized that erbium-doped fiber amplifiers have revolutionized optical fiber communications. EDFAs not only made single-channel, multigigabit-rate, long-distance optical communications possible, but they also opened up a … It is now widely recognized that erbium-doped fiber amplifiers have revolutionized optical fiber communications. EDFAs not only made single-channel, multigigabit-rate, long-distance optical communications possible, but they also opened up a wide variety of additional possibilities Such as soliton generation and transmission and multichannel wavelength-division multiplexing communications. While at AT&T Bell Labs (he is now at Alcatel-Alsthom Recherche in a suburb of Paris, France) Emmanuel Desurvire became heavily involved in and contributed enormously the theoretical and experimental investigation of EDFA characteristics and system applications. His pioneering work has been internationally recognized. In my view, Desurvire is one of those best qualified cover the subject of EDFAs, in Erbium-Doped Fiber Amplifiers: Principles and Applications, he has accepted the challenge. According the author, the purpose of the book is to provide the basic materials of a comprehensive introduction the principles and applications of The book is divided into three major parts, which some extent can be considered independently. Nonetheless, it keeps its cohesion throughout. It provides a thorough understanding of the fundamentals in optical amplification while considering the practical issues related the device and system performance of EDFAs. The first part of the book explores all the fundamental issues related EDFAs. It introduces the main concepts necessary for the modelling of the erbium atomic transition. The analysis is detailed and covers such parameters as field distributions and overlap integrals under different operating conditions. This section and the numerous relevant appendices contain a number of useful generalizations of existing models that are published for the first time. The author also considers the fundamental quantum properties of noise generation and accumulation in single- and multiple-stage amplification of classical light. The analysis discusses in great depth the nature, origin and inevitability of noise associated with optical amplification - it also provides useful engineering formulas for the measurement of the noise introduced by amplification. I found the treatment of noise and photon statistics particularly detailed and original. Researchers working on this subject can benefit enormously from the analysis. The second part is primarily experimental and focuses on EDFA device characteristics. However, when specific characteristics of the erbium transition are discussed, the necessary theoretical modifications and additions, supplementary the general formulations given in the first part, are provided. I found that on the important issue of pulse amplification requirements, the book considers briefly only the special (but very exciting) case of solitons and misses the many problems associated with general pulse amplification. The third and final section of the book, on applications, is primarily concerned with some of the up-to-date linear and nonlinear communication systems and local area networks and the enormous impact that EDFAs have had on their successful implementation. The significance of the EDFAs in optically preamplified receivers is stressed. The most significant digital (linear) and soliton (nonlinear) system experiments performed date are also reviewed. Initations imposed on linear systems by fiber nonlinearities and dispersion are briefly mentioned. The ground that Desurvire sought cover in the third part is quite diverse and could well have been the subject of several separate volumes. Therefore, its inclusion in this book is inevitably of a review type. However, the book clearly points out how and what degree these applications are benefited or enhanced by EDFAs. Overall the book gives one of the most comprehensive and detailed accounts of the physics and fundamental principles of erbium-doped fiber amplifiers published so far. I have not the slightest doubt that the book will be of great help all scientists and engineers working in the field who are struggling understand EDFAs. The unified and in-depth presentation of the subject will benefit in particular researchers and graduate students who are dealing with problems involving optical amplification. The book imparts the fundamental concepts quite skilfully and can be used as collateral reading The sections dealing with modelling and the entire second part could well be used in undergraduate courses. I do not hesitate recommend the book enthusiastically anybody having an interest in EDFAs and their applications.

Mode-Division Multiplexing Over 96 km of Few-Mode Fiber Using Coherent 6$\,\times\,$6 MIMO Processing

2011-11-10

Roland Ryf , Sebastian Randel , A.H. Gnauck +7 more

We report simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber. The channels are successfully … We report simultaneous transmission of six spatial and polarization modes, each carrying 40 Gb/s quadrature-phase-shift-keyed channels over 96 km of a low-differential group delay few-mode fiber. The channels are successfully recovered by offline DSP based on coherent detection and multiple-input multiple-output processing. A penalty of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${<}1.2$</tex> </formula> dB is achieved by using 6 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\,\times\,$</tex> </formula> 6 feed-forward equalizers with 120 taps each. The 6 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\,\times\,$</tex></formula> 6 impulse-response matrix fully characterizing the few-mode fiber is presented, revealing the coupling characteristics between the modes. The results are obtained using mode multiplexers based on phase plates with a mode selectivity of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">${>}28$</tex></formula> dB.

Curvature loss formula for optical fibers

1976-03-01

D. Marcuse

The loss formula for optical fibers with constant radius of curvature of their axes is derived by expressing the field outside of the fiber in terms of a superposition of … The loss formula for optical fibers with constant radius of curvature of their axes is derived by expressing the field outside of the fiber in terms of a superposition of cylindrical outgoing waves. The expansion coefficients are determined by matching the superposition field to the field of the fiber along a cylindrical surface that is tangential to the outer perimeter of the curved fiber. This method is a direct extension of my derivation of the curvature-loss formula for slab guides.

Low-noise erbium-doped fibre amplifier operating at 1.54μm

1987-09-10

R.J. Mears , L. Reekie , I.M. Jauncey +1 more

High gain amplification of up to 28 dB has been observed in a 3m-long erbium-doped fibre. The amplifier has a spectral bandwidth of greater than 300 GHz in the region … High gain amplification of up to 28 dB has been observed in a 3m-long erbium-doped fibre. The amplifier has a spectral bandwidth of greater than 300 GHz in the region of 1.536μm and a measured sensitivity of –42dBm at a bit rate of 140Mbit/s.

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Optical Power Handling Capacity of Low Loss Optical Fibers as Determined by Stimulated Raman and Brillouin Scattering

1972-11-01

R. G. Smith

The effect of stimulated Raman and Brillouin scattering on the power handling capacity of optical fibers is considered and found to be important especially when low loss optical fibers are … The effect of stimulated Raman and Brillouin scattering on the power handling capacity of optical fibers is considered and found to be important especially when low loss optical fibers are used. A critical power below which stimulated effects may be neglected is defined for forward and backward Raman scattering and for backward Brillouin scattering. This critical power is determined by the effective core area A, the small signal attenuation constant of the fiber alpha, and the gain coefficient for the stimulated scattering process (gamma0), by the approximate relation P(crit) approximately 20Aalpha/(gamma0). For a fiber with 20-dB/km attenuation and an area of 10(-7) cm(2)P(crit) approximately 35 mW for stimulated Brillouin scattering. For stimulated Raman scattering P(crit) is approximately two orders of magnitude higher. It is concluded that these effects must be considered in the design of optical communication systems using low loss fibers.

High-gain erbium-doped traveling-wave fiber amplifier

1987-11-01

E. Desurvire , J.R. Simpson , P. C. Becker

Traveling-wave amplification of a lambda = 1.53 microm signal with +22-dB gain is achieved at 295 K in an Er(3+)-doped single-mode fiber using a lambda = 514.5 nm pump source. … Traveling-wave amplification of a lambda = 1.53 microm signal with +22-dB gain is achieved at 295 K in an Er(3+)-doped single-mode fiber using a lambda = 514.5 nm pump source. The optimum fiber length for maximum gain is determined experimentally. A limit in signal-to-noise ratio that is due to concurrent amplification of spontaneous emission is observed. By cooling the fiber to 77 K, the amplifier gain is increased to +29 dB as a result of depopulation of the lower laser level.

Multimode Theory of Graded-Core Fibers

1973-11-01

D. Gloge , E. A. J. Marcatili

New technologies of fiber manufacture and a demand for unusual fiber qualities in communication systems have intensified the interest in a comprehensive theory of multimode fibers with nonuniform index distributions. … New technologies of fiber manufacture and a demand for unusual fiber qualities in communication systems have intensified the interest in a comprehensive theory of multimode fibers with nonuniform index distributions. This paper deals with a general class of circular symmetric profiles which comprise the parabolic distribution and the abrupt core-cladding index step as special cases. We obtain general results of useful simplicity for the impulse response, the mode volume, and the near- and far-field power distributions. We suggest a modified parabolic distribution for best equalization of mode delay differences. The effective width of the resulting impulse is more than four times smaller than that produced by the parabolic profile. Of course, practical manufacturing tolerances are likely to influence this distribution. A relation is derived between the maximum index error and the impulse response.

Nonlinear Optics for High-Speed Digital Information Processing

1999-11-19

D. Cotter , R.J. Manning , K.J. Blow +6 more

Recent advances in developing nonlinear optical techniques for processing serial digital information at high speed are reviewed. The field has been transformed by the advent of semiconductor nonlinear devices capable … Recent advances in developing nonlinear optical techniques for processing serial digital information at high speed are reviewed. The field has been transformed by the advent of semiconductor nonlinear devices capable of operation at 100 gigabits per second and higher, well beyond the current speed limits of commercial electronics. These devices are expected to become important in future high-capacity communications networks by allowing digital regeneration and other processing functions to be performed on data signals “on the fly” in the optical domain.

PMD fundamentals: Polarization mode dispersion in optical fibers

2000-04-25

J. P. Gordon , H. Kogelnik

This paper reviews the fundamental concepts and basic theory of polarization mode dispersion (PMD) in optical fibers. It introduces a unified notation and methodology to link the various views and … This paper reviews the fundamental concepts and basic theory of polarization mode dispersion (PMD) in optical fibers. It introduces a unified notation and methodology to link the various views and concepts in Jones space and Stokes space. The discussion includes the relation between Jones vectors and Stokes vectors, rotation matrices, the definition and representation of PMD vectors, the laws of infinitesimal rotation, and the rules for PMD vector concatenation.

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Advanced Optical Modulation Formats

2006-05-01

Peter J. Winzer , René-Jean Essiambre

Fiber-optic communication systems form the high-capacity transport infrastructure that enables global broadband data services and advanced Internet applications. The desire for higher per-fiber transport capacities and, at the same time, … Fiber-optic communication systems form the high-capacity transport infrastructure that enables global broadband data services and advanced Internet applications. The desire for higher per-fiber transport capacities and, at the same time, the drive for lower costs per end-to-end transmitted information bit has led to optically routed networks with high spectral efficiencies. Among other enabling technologies, advanced optical modulation formats have become key to the design of modern wavelength division multiplexed (WDM) fiber systems. In this paper, we review optical modulation formats in the broader context of optically routed WDM networks. We discuss the generation and detection of multigigabit/s intensity- and phase-modulated formats, and highlight their resilience to key impairments found in optical networking, such as optical amplifier noise, multipath interference, chromatic dispersion, polarization-mode dispersion, WDM crosstalk, concatenated optical filtering, and fiber nonlinearity

Space-division multiplexing: the next frontier in optical communication

2014-12-23

Guifang Li , Neng Bai , Ningbo Zhao +1 more

Space-division multiplexing (SDM) uses multiplicity of space channels to increase capacity for optical communication. It is applicable for optical communication in both free space and guided waves. This paper focuses … Space-division multiplexing (SDM) uses multiplicity of space channels to increase capacity for optical communication. It is applicable for optical communication in both free space and guided waves. This paper focuses on SDM for fiber-optic communication using few-mode fibers or multimode fibers, in particular on the critical challenge of mode crosstalk. Multiple-input–multiple-output (MIMO) equalization methods developed for wireless communication can be applied as an electronic method to equalize mode crosstalk. Optical approaches, including differential modal group delay management, strong mode coupling, and multicore fibers, are necessary to bring the computational complexity for MIMO mode crosstalk equalization to practical levels. Progress in passive devices, such as (de)multiplexers, and active devices, such as amplifiers and switches, which are considered straightforward challenges in comparison with mode crosstalk, are reviewed. Finally, we present the prospects for SDM in optical transmission and networking.

Solitons in optical communications

1996-04-01

H. A. Haus , William S. Wong

The history of the proposal that solitons be used for optical fiber communications and of the technical developments toward making soliton transmission practical is reviewed. The causes of bit errors … The history of the proposal that solitons be used for optical fiber communications and of the technical developments toward making soliton transmission practical is reviewed. The causes of bit errors in long-distance soliton transmission are presented and the methods for reducing them are described. A perturbation theory suited for soliton analysis is developed. Current status and future prospects of long-distance repeaterless fiber communications are stated.

Coherent optical OFDM: theory and design

2008-01-01

William Shieh , Hongchun Bao , Yun Tang

Coherent optical OFDM (CO-OFDM) has recently been proposed and the proof-of-concept transmission experiments have shown its extreme robustness against chromatic dispersion and polarization mode dispersion. In this paper, we first … Coherent optical OFDM (CO-OFDM) has recently been proposed and the proof-of-concept transmission experiments have shown its extreme robustness against chromatic dispersion and polarization mode dispersion. In this paper, we first review the theoretical fundamentals for CO-OFDM and its channel model in a 2x2 MIMO-OFDM representation. We then present various design choices for CO-OFDM systems and perform the nonlinearity analysis for RF-to-optical up-converter. We also show the receiver-based digital signal processing to mitigate self-phase-modulation (SPM) and Gordon-Mollenauer phase noise, which is equivalent to the midspan phase conjugation.

Coherent optical orthogonal frequency division multiplexing

2006-05-11

William Shieh , C.R.N. Athaudage

Coherent optical orthogonal frequency division multiplexing is proposed to combat dispersion in optical media. It is shown that optical-signal-to-noise ratio penalty at 10 Gbit/s is maintained below 2 dB for … Coherent optical orthogonal frequency division multiplexing is proposed to combat dispersion in optical media. It is shown that optical-signal-to-noise ratio penalty at 10 Gbit/s is maintained below 2 dB for 3000 km transmission of standard-singlemode fibre without dispersion compensation.

Spectrum-efficient and scalable elastic optical path network: architecture, benefits, and enabling technologies

2009-11-01

Masahiko Jinno , H. Takara , Bartłomiej Kozicki +3 more

The sustained growth of data traffic volume calls for an introduction of an efficient and scalable transport platform for links of 100 Gb/s and beyond in the future optical network. … The sustained growth of data traffic volume calls for an introduction of an efficient and scalable transport platform for links of 100 Gb/s and beyond in the future optical network. In this article, after briefly reviewing the existing major technology options, we propose a novel, spectrum- efficient, and scalable optical transport network architecture called SLICE. The SLICE architecture enables sub-wavelength, superwavelength, and multiple-rate data traffic accommodation in a highly spectrum-efficient manner, thereby providing a fractional bandwidth service. Dynamic bandwidth variation of elastic optical paths provides network operators with new business opportunities offering cost-effective and highly available connectivity services through time-dependent bandwidth sharing, energy-efficient network operation, and highly survivable restoration with bandwidth squeezing. We also discuss an optical orthogonal frequency-division multiplexing-based flexible-rate transponder and a bandwidth-variable wavelength cross-connect as the enabling technologies of SLICE concept. Finally, we present the performance evaluation and technical challenges that arise in this new network architecture.

Coherent detection in optical fiber systems

2008-01-01

Ezra Ip , Alan Pak Tao Lau , Daniel J. F. Barros +1 more

The drive for higher performance in optical fiber systems has renewed interest in coherent detection. We review detection methods, including noncoherent, differentially coherent, and coherent detection, as well as a … The drive for higher performance in optical fiber systems has renewed interest in coherent detection. We review detection methods, including noncoherent, differentially coherent, and coherent detection, as well as a hybrid method. We compare modulation methods encoding information in various degrees of freedom (DOF). Polarization-multiplexed quadrature-amplitude modulation maximizes spectral efficiency and power efficiency, by utilizing all four available DOF, the two field quadratures in the two polarizations. Dual-polarization homodyne or heterodyne downconversion are linear processes that can fully recover the received signal field in these four DOF. When downconverted signals are sampled at the Nyquist rate, compensation of transmission impairments can be performed using digital signal processing (DSP). Linear impairments, including chromatic dispersion and polarization-mode dispersion, can be compensated quasi-exactly using finite impulse response filters. Some nonlinear impairments, such as intra-channel four-wave mixing and nonlinear phase noise, can be compensated partially. Carrier phase recovery can be performed using feedforward methods, even when phase-locked loops may fail due to delay constraints. DSP-based compensation enables a receiver to adapt to time-varying impairments, and facilitates use of advanced forward-error-correction codes. We discuss both single- and multi-carrier system implementations. For a given modulation format, using coherent detection, they offer fundamentally the same spectral efficiency and power efficiency, but may differ in practice, because of different impairments and implementation details. With anticipated advances in analog-to-digital converters and integrated circuit technology, DSP-based coherent receivers at bit rates up to 100 Gbit/s should become practical within the next few years.

Weakly Guiding Fibers

1971-10-01

D. Gloge

Thin glass fibers imbedded into a glass cladding of slightly lower refractive index represent a promising medium for optical communication. This article presents simple formulas and functions for the fiber … Thin glass fibers imbedded into a glass cladding of slightly lower refractive index represent a promising medium for optical communication. This article presents simple formulas and functions for the fiber parameters as a help for practical design work. It considers the propagation constant, mode delay, the cladding field depth, and the power distribution in the fiber cross section. Plots vs frequency of these parameters are given for 70 modes.

Digital filters for coherent optical receivers

2008-01-01

Seb J. Savory

Digital filters underpin the performance of coherent optical receivers which exploit digital signal processing (DSP) to mitigate transmission impairments. We outline the principles of such receivers and review our experimental … Digital filters underpin the performance of coherent optical receivers which exploit digital signal processing (DSP) to mitigate transmission impairments. We outline the principles of such receivers and review our experimental investigations into compensation of polarization mode dispersion. We then consider the details of the digital filtering employed and present an analytical solution to the design of a chromatic dispersion compensating filter. Using the analytical solution an upper bound on the number of taps required to compensate chromatic dispersion is obtained, with simulation revealing an improved bound of 2.2 taps per 1000ps/nm for 10.7GBaud data. Finally the principles of digital polarization tracking are outlined and through simulation, it is demonstrated that 100krad/s polarization rotations could be tracked using DSP with a clock frequency of less than 500MHz.

Capacity Trends and Limits of Optical Communication Networks

2012-03-19

René-Jean Essiambre , R.W. Tkach

Since the first deployments of fiber-optic communication systems three decades ago, the capacity carried by a single-mode optical fiber has increased by a staggering 10 000 times. Most of the … Since the first deployments of fiber-optic communication systems three decades ago, the capacity carried by a single-mode optical fiber has increased by a staggering 10 000 times. Most of the growth occurred in the first two decades with growth slowing to ten times in the last decade. Over the same three decades, network traffic has increased by a much smaller factor of 100, but with most of the growth occurring in the last few years, when data started dominating network traffic. At the current growth rate, the next factor of 100 in network traffic growth will occur within a decade. The large difference in growth rates between the delivered fiber capacity and the traffic demand is expected to create a capacity shortage within a decade. The first part of the paper recounts the history of traffic and capacity growth and extrapolations for the future. The second part looks into the technological challenges of growing the capacity of single-mode fibers by presenting a capacity limit estimate of standard and advanced single-mode optical fibers. The third part presents elementary capacity considerations for transmission over multiple transmission modes and how it compares to a single-mode transmission. Finally, the last part of the paper discusses fibers supporting multiple spatial modes, including multimode and multicore fibers, and the role of digital processing techniques. Spatial multiplexing in fibers is expected to enable system capacity growth to match traffic growth in the next decades.

Advances in photonic packet switching: an overview

2000-01-01

Shun Yao , Biswanath Mukherjee , Sudhir Dixit

The current fast-growing Internet traffic is demanding more and more network capacity every day. The concept of wavelength-division multiplexing has provided us an opportunity to multiply network capacity. Current optical … The current fast-growing Internet traffic is demanding more and more network capacity every day. The concept of wavelength-division multiplexing has provided us an opportunity to multiply network capacity. Current optical switching technologies allow us to rapidly deliver the enormous bandwidth of WDM networks. Photonic packet switching offers high-speed, data rate/format transparency, and configurability, which are some of the important characteristics needed in future networks supporting different forms of data. In this article we present some of the critical issues involved in designing and implementing all-optical packet-switched networks.

Limitations on lightwave communications imposed by optical-fiber nonlinearities

1990-01-01

A.R. Chraplyvy

Optical nonlinearities in the context of lightwave systems limitations are described. The nature and severity of system degradation due to stimulated Raman scattering, carrier-induced phase noise, stimulated Brillouin scattering, and … Optical nonlinearities in the context of lightwave systems limitations are described. The nature and severity of system degradation due to stimulated Raman scattering, carrier-induced phase noise, stimulated Brillouin scattering, and four-photon mixing are discussed. The system power limitations are plotted as a function of a number of wavelength-multiplexed channels. Methods for scaling these results with changes in system parameters are presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>

OFDM for Optical Communications

2009-02-01

Jean Armstrong

Orthogonal frequency division multiplexing (OFDM) is a modulation technique which is now used in most new and emerging broadband wired and wireless communication systems because it is an effective solution … Orthogonal frequency division multiplexing (OFDM) is a modulation technique which is now used in most new and emerging broadband wired and wireless communication systems because it is an effective solution to intersymbol interference caused by a dispersive channel. Very recently a number of researchers have shown that OFDM is also a promising technology for optical communications. This paper gives a tutorial overview of OFDM highlighting the aspects that are likely to be important in optical applications. To achieve good performance in optical systems OFDM must be adapted in various ways. The constraints imposed by single mode optical fiber, multimode optical fiber and optical wireless are discussed and the new forms of optical OFDM which have been developed are outlined. The main drawbacks of OFDM are its high peak to average power ratio and its sensitivity to phase noise and frequency offset. The impairments that these cause are described and their implications for optical systems discussed.

Fiber-based optical parametric amplifiers and their applications

2002-05-01

Jonás Hansryd , Peter A. Andrekson , M. Westlund +2 more

An applications-oriented review of optical parametric amplifiers in fiber communications is presented. The emphasis is on parametric amplifiers in general and single pumped parametric amplifiers in particular. While a theoretical … An applications-oriented review of optical parametric amplifiers in fiber communications is presented. The emphasis is on parametric amplifiers in general and single pumped parametric amplifiers in particular. While a theoretical framework based on highly efficient four-photon mixing is provided, the focus is on the intriguing applications enabled by the parametric gain, such as all-optical signal sampling, time-demultiplexing, pulse generation, and wavelength conversion. As these amplifiers offer high gain and low noise at arbitrary wavelengths with proper fiber design and pump wavelength allocation, they are also candidate enablers to increase overall wavelength-division-multiplexing system capacities similar to the more well-known Raman amplifiers. Similarities and distinctions between Raman and parametric amplifiers are also addressed. Since the first fiber-based parametric amplifier experiments providing net continuous-wave gain in the for the optical fiber communication applications interesting 1.5-/spl mu/m region were only conducted about two years ago, there is reason to believe that substantial progress may be made in the future, perhaps involving "holey fibers" to further enhance the nonlinearity and thus the gain. This together with the emergence of practical and inexpensive high-power pump lasers may in many cases prove fiber-based parametric amplifiers to be a desired implementation in optical communication systems.

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Power efficient optical OFDM

2006-03-16

Jean Armstrong , Arthur J. Lowery

A new technique for using orthogonal frequency division multiplexing (OFDM) in optical systems is presented. Clipped OFDM is derived from a bipolar OFDM waveform by setting the negative values to … A new technique for using orthogonal frequency division multiplexing (OFDM) in optical systems is presented. Clipped OFDM is derived from a bipolar OFDM waveform by setting the negative values to zero. It has an optical efficiency 8 dB better than DC biased OFDM. If only the odd OFDM subcarriers are modulated, the clipping noise is orthogonal to the wanted signal.

Hardware-Efficient Coherent Digital Receiver Concept With Feedforward Carrier Recovery for $M$-QAM Constellations

2009-04-01

Timo Pfau , Sebastian Hoffmann , R. Noé

This paper presents a novel digital feedforward carrier recovery algorithm for arbitrary M -ary quadrature amplitude modulation (M-QAM) constellations in an intradyne coherent optical receiver. The approach does … This paper presents a novel digital feedforward carrier recovery algorithm for arbitrary M -ary quadrature amplitude modulation (M-QAM) constellations in an intradyne coherent optical receiver. The approach does not contain any feedback loop and is therefore highly tolerant against laser phase noise. This is crucial, especially for higher order QAM constellations, which inherently have a smaller phase noise tolerance due to the lower spacing between adjacent constellation points. In addition to the mathematical description of the proposed carrier recovery algorithm also a possible hardware-efficient implementation in a parallelized system is presented and the performance of the algorithm is evaluated by Monte Carlo simulations for square 4-QAM (QPSK), 16-QAM, 64-QAM, and 256-QAM. For the simulations ASE noise and laser phase noise are considered as well as analog-to-digital converter (ADC) and internal resolution effects. For a 1 dB penalty at BER = 10 -3 , linewidth times symbol duration products of 4.1 x 10 -4 (4-QAM), 1.4 x 10 -4 (16-QAM), 4.0 x 10 -5 (64-QAM) and 8.0 x 10 -6 (256-QAM) are tolerable.

Exact and Approximate Construction of Digital Phase Modulations by Superposition of Amplitude Modulated Pulses (AMP)

1986-02-01

Ph. Laurent

Minimum shift keying and offset QPSK are two well-known modulations which can be interpreted as a set of time/phase-shifted AM pulses. We show in this paper that any constant amplitude … Minimum shift keying and offset QPSK are two well-known modulations which can be interpreted as a set of time/phase-shifted AM pulses. We show in this paper that any constant amplitude binary phase modulation can also be expressed as a sum of a finite number of time limited amplitude modulated pulses (AMP decomposition). New methods for computing autocorrelation and power frequency spectrum are derived, which give very simple results for half-integer index modulations. We also show that the signal can be built with good accuracy using only one optimized pulse ("main pulse"). This synthesis is particularly satisfactory for modulations that have good spectral characteristics and/ or low index.

Theoretical description of transient stimulated Raman scattering in optical fibers

1989-01-01

K.J. Blow , David Wood

The authors derive a single-wave equation which describes transient stimulated Raman scattering in optical fibers. The equation is valid for forward traveling waves whose bandwidths are less than approximately=1/3 the … The authors derive a single-wave equation which describes transient stimulated Raman scattering in optical fibers. The equation is valid for forward traveling waves whose bandwidths are less than approximately=1/3 the carrier frequency. It correctly conserves a classical photon number and not the total optical energy as is appropriate for Raman scattering problems. From this equation, the authors derive a formula for the small-signal gain spectrum which includes the effects of Raman scattering, four-wave mixing, and modulational instabilities. Examples of numerical integrations are given which show the generation of short soliton pulses from the nonlinear evolution of a noise band around a continuous wave pump.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>

WDM-compatible mode-division multiplexing on a silicon chip

2014-01-15

Lian-Wee Luo , Noam Ophir , Christine P. Chen +4 more

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Capacity Limits of Optical Fiber Networks

2010-02-01

René-Jean Essiambre , Gerhard Kramer , Peter J. Winzer +2 more

We describe a method to estimate the capacity limit of fiber-optic communication systems (or ¿fiber channels¿) based on information theory. This paper is divided into two parts. Part 1 reviews … We describe a method to estimate the capacity limit of fiber-optic communication systems (or ¿fiber channels¿) based on information theory. This paper is divided into two parts. Part 1 reviews fundamental concepts of digital communications and information theory. We treat digitization and modulation followed by information theory for channels both without and with memory. We provide explicit relationships between the commonly used signal-to-noise ratio and the optical signal-to-noise ratio. We further evaluate the performance of modulation constellations such as quadrature-amplitude modulation, combinations of amplitude-shift keying and phase-shift keying, exotic constellations, and concentric rings for an additive white Gaussian noise channel using coherent detection. Part 2 is devoted specifically to the "fiber channel.'' We review the physical phenomena present in transmission over optical fiber networks, including sources of noise, the need for optical filtering in optically-routed networks, and, most critically, the presence of fiber Kerr nonlinearity. We describe various transmission scenarios and impairment mitigation techniques, and define a fiber channel deemed to be the most relevant for communication over optically-routed networks. We proceed to evaluate a capacity limit estimate for this fiber channel using ring constellations. Several scenarios are considered, including uniform and optimized ring constellations, different fiber dispersion maps, and varying transmission distances. We further present evidences that point to the physical origin of the fiber capacity limitations and provide a comparison of recent record experiments with our capacity limit estimation.

IPACT a dynamic protocol for an Ethernet PON (EPON)

2002-01-01

Glen Kramer , Biswanath Mukherjee , G. Pesavento

We investigate design issues for access networks based on passive optical network technology. A PON based on polling, with data encapsulated in Ethernet frames, possesses many desirable qualities, such as … We investigate design issues for access networks based on passive optical network technology. A PON based on polling, with data encapsulated in Ethernet frames, possesses many desirable qualities, such as dynamic bandwidth distribution, use of a single downstream and a single upstream wavelength, ability to provision a fractional wavelength capacity to each user, and ease of adding a new user. To support dynamic bandwidth distribution, we propose an interleaved polling algorithm called IPACT. We also suggest a scheme for in-band signaling that allows using a single wavelength for both downstream data and control message transmission. To obtain realistic simulation results, we generated synthetic traffic that exhibits the properties of self-similarity and long-range dependence. We then analyzed the network performance under varying offered loads.

Elastic optical networking: a new dawn for the optical layer?

2012-02-01

Ori Gerstel , Masahiko Jinno , Andrew Lord +1 more

Optical networks are undergoing significant changes, fueled by the exponential growth of traffic due to multimedia services and by the increased uncertainty in predicting the sources of this traffic due … Optical networks are undergoing significant changes, fueled by the exponential growth of traffic due to multimedia services and by the increased uncertainty in predicting the sources of this traffic due to the ever changing models of content providers over the Internet. The change has already begun: simple on-off modulation of signals, which was adequate for bit rates up to 10 Gb/s, has given way to much more sophisticated modulation schemes for 100 Gb/s and beyond. The next bottleneck is the 10-year-old division of the optical spectrum into a fixed "wavelength grid," which will no longer work for 400 Gb/s and above, heralding the need for a more flexible grid. Once both transceivers and switches become flexible, a whole new elastic optical networking paradigm is born. In this article we describe the drivers, building blocks, architecture, and enabling technologies for this new paradigm, as well as early standardization efforts.

Optical phase-shift-keyed transmission

2005-01-01

A.H. Gnauck , Peter J. Winzer

Differential-phase-shift keying (DPSK) has recently been used to reach record distances in long-haul lightwave communication systems. This paper will review theoretical, as well as implementation, aspects of DPSK, and discuss … Differential-phase-shift keying (DPSK) has recently been used to reach record distances in long-haul lightwave communication systems. This paper will review theoretical, as well as implementation, aspects of DPSK, and discuss experimental results.

Digital Coherent Optical Receivers: Algorithms and Subsystems

2010-05-26

Seb J. Savory

Digital coherent receivers have caused a revolution in the design of optical transmission systems, due to the subsystems and algorithms embedded within such a receiver. After giving a high-level overview … Digital coherent receivers have caused a revolution in the design of optical transmission systems, due to the subsystems and algorithms embedded within such a receiver. After giving a high-level overview of the subsystems, the optical front end, the analog-to-digital converter (ADC) and the digital signal processing (DSP) algorithms, which relax the tolerances on these subsystems are discussed. Attention is then turned to the compensation of transmission impairments, both static and dynamic. The discussion of dynamic-channel equalization, which forms a significant part of the paper, includes a theoretical analysis of the dual-polarization constant modulus algorithm, where the control surfaces several different equalizer algorithms are derived, including the constant modulus, decision-directed, trained, and the radially directed equalizer for both polarization division multiplexed quadriphase shift keyed (PDM-QPSK) and 16 level quadrature amplitude modulation (PDM-16-QAM). Synchronization algorithms employed to recover the timing and carrier phase information are then examined, after which the data may be recovered. The paper concludes with a discussion of the challenges for future coherent optical transmission systems.

Compensation of Dispersion and Nonlinear Impairments Using Digital Backpropagation

2008-10-01

Ezra Ip , Joseph M. Kahn

Optical fiber transmission is impacted by linear and nonlinear impairments. We study the use of digital backpropagation (BP) in conjunction with coherent detection to jointly mitigate dispersion and fiber nonlinearity. … Optical fiber transmission is impacted by linear and nonlinear impairments. We study the use of digital backpropagation (BP) in conjunction with coherent detection to jointly mitigate dispersion and fiber nonlinearity. We propose a noniterative asymmetric split-step Fourier method (SSFM) for solving the inverse nonlinear Schrodinger equation (NLSE). Using simulation results for RZ-QPSK transmitted over terrestrial systems with inline amplification and dispersion compensation, we obtain heuristics for the step size and sampling rate requirements, as well as the optimal dispersion map.

Ultimate low-loss single-mode fibre at 1.55 μm

1979-02-15

T. Miya , Y. Terunuma , T. Hosaka +1 more

A very low loss single-mode fibre with a minimum loss of 0.20 dB/km at a wavelength of 1.55 μm is attained; this loss reaches the ultimate lower loss limit of … A very low loss single-mode fibre with a minimum loss of 0.20 dB/km at a wavelength of 1.55 μm is attained; this loss reaches the ultimate lower loss limit of silica-based optical glass fibre. The loss mechanism is also discussed.

Fundamentals of Coherent Optical Fiber Communications

2015-08-03

K. Kikuchi

The recently developed digital coherent receiver enables us to employ a variety of spectrally efficient modulation formats such as M-ary phase-shift keying and quadrature-amplitude modulation. Moreover, in the digital domain, … The recently developed digital coherent receiver enables us to employ a variety of spectrally efficient modulation formats such as M-ary phase-shift keying and quadrature-amplitude modulation. Moreover, in the digital domain, we can equalize all linear transmission impairments such as group-velocity dispersion and polarization-mode dispersion of transmission fibers, because coherent detection preserves the phase information of the optical signal. This paper reviews the history of research and development related to coherent optical communications and describes the principle of coherent detection, including its quantum-noise characteristics. In addition, it discusses the role of digital signal processing in mitigating linear transmission impairments, estimating the carrier phase, and tracking the state of polarization of the signal in coherent receivers.

Solitons in Optical Communications

1995-04-27

Akira Hasegawa , Yuji Kodama

Abstract Solitons are a fascinating topic for study and a major source of interest for potential application in optical communication. Possibly the first observation of a soliton occurred in 1838 … Abstract Solitons are a fascinating topic for study and a major source of interest for potential application in optical communication. Possibly the first observation of a soliton occurred in 1838 and was made by a clerical gentleman riding a horse along a canal towpath. When a barge under tow came to a stop alongside him the bow wave did not stop, but continued to travel on its own for several miles with no change in shape. At the time this unusual phenomenon was not understood and remained unexplained. Interest was revived with the development of optical fibres and the realisation that at the high intensities possible in their very small cores the onset of non-linear effects could modify the propagation characteristics in a significant way. In a seminal paper in 1973 Hasegawa and Tappert solved a non-linear Schrodinger equation for fibre propagation and found solutions for solitary waves, i.e. solitons. Since then advances have been very rapid resulting in a much better understanding of a wide variety of soliton effects, and, crucially, the realisation that soliton propagation can be used to potentially great advantage in practical long-distance systems. There is, as a result, a wealth of theoretical and experimental research in progress all over the world. At NTT (Japan) a pule-code-modulated soliton train has been transmitted at 10Gbit/s over one million kilometres with zero error! Perhaps all long-distance, large bandwidth communication problems have been solved for ever. This book gives a clear account of the theory and mathematics of solitons travelling in optical fibres. It is written by the authority on the subject.

Applications of Nonlinear Fiber Optics

2001-01-01

Fiber-optic transmission and networking: the previous 20 and the next 20 years [Invited]

2018-08-31

Peter J. Winzer , David T. Neilson , A.R. Chraplyvy

Celebrating the 20th anniversary of Optics Express, this paper reviews the evolution of optical fiber communication systems, and through a look at the previous 20 years attempts to extrapolate fiber-optic … Celebrating the 20th anniversary of Optics Express, this paper reviews the evolution of optical fiber communication systems, and through a look at the previous 20 years attempts to extrapolate fiber-optic technology needs and potential solution paths over the coming 20 years. Well aware that 20-year extrapolations are inherently associated with great uncertainties, we still hope that taking a significantly longer-term view than most texts in this field will provide the reader with a broader perspective and will encourage the much needed out-of-the-box thinking to solve the very significant technology scaling problems ahead of us. Focusing on the optical transport and switching layer, we cover aspects of large-scale spatial multiplexing, massive opto-electronic arrays and holistic optics-electronics-DSP integration, as well as optical node architectures for switching and multiplexing of spatial and spectral superchannels.

Nonlinear Fiber Optics

2000-01-01

Govind P. Agrawal

Nonlinear fiber optics concerns with the nonlinear optical phenomena occurring inside optical fibers. Although the field ofnonlinear optics traces its beginning to 1961, when a ruby laser was first used … Nonlinear fiber optics concerns with the nonlinear optical phenomena occurring inside optical fibers. Although the field ofnonlinear optics traces its beginning to 1961, when a ruby laser was first used to generate the second-harmonic radiation inside a crystal [1], the use ofoptical fibers as a nonlinear medium became feasible only after 1970 when fiber losses were reduced to below 20 dB/km [2]. Stimulated Raman and Brillouin scatterings in single-mode fibers were studied as early as 1972 [3] and were soon followed by the study of other nonlinear effects such as self- and crossphase modulation and four-wave mixing [4]. By 1989, the field ofnonlinear fiber optics has advanced enough that a whole book was devoted to it [5]. This book or its second edition has been translated into Chinese, Japanese, and Russian languages, attesting to the worldwide activity in the field of nonlinear fiber optics.

Joint chromatic dispersion, differential group delay compensation, and timing recovery scheme for Nyquist optical transmission systems

2025-06-25

Jialin You , Kunfeng Liu | Optical Engineering

Carrier-Based Pulse Width Modulation and Operation Limits

2025-06-24

Dorin O. Neacșu | CRC Press eBooks

Complex-Valued Deep Neural Network Equalizer with Attention Mechanism for Photonics-Aided 400 GHz PS-16QAM System

2025-06-24

Long Chen , Fan Liu , Ziteng Yang +1 more | Applied Optics

Thermal modeling and performance analysis of nested-ring doping in high-power LMA-TDFLs

2025-06-24

Mohamed Zaki , Hamid Jouah , Mostafa Abouricha +1 more | Optical Fiber Technology

Optimization of nonlinear effect suppression in gain-switched Raman fiber lasers for enhanced SRS conversion efficiency

2025-06-24

Yù Zhang , Wei-Shen Zhan , Peiqing Zhang +2 more | Optics Express

Multi-Link Fragmentation-Aware Deep Reinforcement Learning RSA Algorithm in Elastic Optical Network

2025-06-22

Jing Jiang , Y. S Su , Jingchi Cheng +1 more | Photonics

Deep reinforcement learning has been extensively applied for resource allocation in elastic optical networks. However, many studies focus on link-level state analysis and rarely discuss the influence between links, which … Deep reinforcement learning has been extensively applied for resource allocation in elastic optical networks. However, many studies focus on link-level state analysis and rarely discuss the influence between links, which may affect the performance of allocation algorithms. In this paper, we propose a multi-link fragmentation deep reinforcement learning-based routing and spectrum allocation algorithm (MFDRL-RSA). We number the links using a breadth-first numbering algorithm. Based on the numbering results, high-frequency links are selected to construct the network state matrix that reflects the resource distribution. According to the state matrix, we calculate a multi-link fragmentation degree, quantifying resource fragmentation within a representative subset of network. The MFDRL-RSA algorithm enhances the accuracy of the agent’s decision-making by incorporating it into the reward function, thereby improving its performance in routing decisions, which contributes to the overall allocation performance. Simulation results show that MFDRL-RSA achieves lower blocking rates compared to the reference algorithms, with reductions of 16.34%, 13.01%, and 7.42% in the NSFNET network and 19.33%, 15.17%, and 9.95% in the Cost-239 network. It also improves spectrum utilization by 12.28%, 9.83%, and 6.32% in NSFNET and by 13.92%, 11.55%, and 8.26% in Cost-239.

High-efficiency all-optical wavelength conversion via polarization-insensitive four-wave mixing for 10 Gbps digital signals

2025-06-21

Wen-Hai Tan , Zhenhong Wang , Jianhua Ji +1 more | Optics & Laser Technology

The Analysis of Resource Efficiencies for the Allocation Methods Applied in the Proposed OAM&WDM-PON Architecture

2025-06-21

Rastislav Róka | Photonics

Infrastructures of access networks that mostly exploit the optical fiber medium effectively utilizing wavelength division multiplexing techniques play a key role in advanced F5G fixed networks. The orbital angular momentum … Infrastructures of access networks that mostly exploit the optical fiber medium effectively utilizing wavelength division multiplexing techniques play a key role in advanced F5G fixed networks. The orbital angular momentum technique is highly promising for use within passive optical networks to further increase transmission capacities. So, the utilization of common network resources in wavelength and optical domains will be more important. The main purpose of this paper is to present an analysis of resource efficiencies for various allocation methods applied in the proposed OAM&WDM-PON architecture with a conventional point-to-multipoint topology. This contribution introduces novel static, dynamic and dynamic customized allocation methods for a proposed network design with the utilization of only passive optical splitters in remote nodes. These WDM and OAM channel allocation methods are oriented towards minimizing the number of working wavelengths and OAM channels that will be used for compliance with customers’ requests for data transmitting in the proposed point-to-multipoint OAM&WDM-PON architecture. For analyzing and evaluating the considered allocation methods, a simulation model related to the proposed P2MP OAM&WDM-PON design realized in the MATLAB (R2022A) programming environment is presented with acquired simulation results. Finally, resource efficiencies of the presented novel allocation methods are evaluated from the viewpoint of application in future OAM&WDM-PONs.

Optical fiber nonlinear neural compensation based on generalized mutual information cost function

2025-06-21

Zekun Niu , Lyu Li , Hang Yang +2 more | Optical Fiber Technology

Three-Dimensional Trident Edge Coupler with Ultralow-Loss and Broad Bandwidth for Standard Single-Mode Fiber

2025-06-20

Zhijun Zhu , Wencheng Yue , Yan Cai +1 more | Journal of the Optical Society of America B

Enhancing Fault Detection and Localization in Passive Optical Networks Through Advanced Deep Learning and Explainability Techniques

2025-06-19

Kamlesh Kumar Soothar , Yuanxiang Chen , Kamran Ali Memon +3 more | Arabian Journal for Science and Engineering

Advanced modulation format indicator for nonlinear impairments mitigation in optical transmission system: a comprehensive analytical and experimental-based approach

2025-06-18

Farman Ali , Muhammad Arsalan , Tanzeel Ur Rahman +5 more | Computers & Electrical Engineering

Memory-efficient MLSE with pre-decision-driven pruning and metric sharing for bandwidth-constrained baud-rate sampling coherent optical interconnects

2025-06-17

chenchen wang , Zhipei Li , Ze Dong +7 more | Optics Express

Detecting high-dimensional time-bin entanglement in fiber-loop systems

2025-06-17

NULL AUTHOR_ID | Physical review. A/Physical review, A

Cost-effective 200-Gbps/λ coherent PON enabled by DFB lasers and a pilot-based carrier recovery

2025-06-17

Yifan Chen , Jianjun Yu , Chen Wang +5 more | Science China Information Sciences

Nonlinear FWM effects management and FWM system performance analysis in ultra wide optical wavelength division multiplexing systems

2025-06-16

G. Ramkumar , G. D. Vignesh , Manimaran Arjunan +4 more | Journal of Optical Communications

Abstract This paper has highlighted the nonlinear FWM (fourwave mixing) effects management and FWM system performance analysis in ultra wide optical wavelength division multiplexing systems. The optical output power is … Abstract This paper has highlighted the nonlinear FWM (fourwave mixing) effects management and FWM system performance analysis in ultra wide optical wavelength division multiplexing systems. The optical output power is measured with the fiber propagation length based on first/second signals and first/second induced signals. The FWM output power is demonstrated with channel spacing, dispersion coefficient and input signal power based on various modulation techniques. FWM system signal per noise ratio and BER are clarified with the dispersion coefficient with different modulation techniques in FWM system. Maximum transmit power per channel is investigated with the propagation fiber length with different modulation techniques. Maximum mixing efficiency is measured with the fiber dispersion coefficients and channel spacing. Normalized conversion efficiency is demonstrated against the operating wavelength. The FWM power penalty is analyzed and measured against input signal power and total fiber dispersion coefficient. Total system bit rate and total system disperstion are clarified in relation to input signal power with/without chirped FBG with NRZ-PSK modulation technique.

Seven-core fiber optical palm

2025-06-16

Kai Zhang , Youxing Li , Tingting Yuan +5 more | Optics Express

Experimental investigation of evolution of dynamics in short-resonant-cavity DFB laser with optical feedback

2025-06-16

Wenchao Chen , Yuanyuan Guo , Zhiwei Jia +3 more | Optics & Laser Technology

Evaluation of optimized praseodymium-thulium doped O+E band hybrid fiber amplifier in a CWDM optical communication link

2025-06-15

Krishna Sarma , Mohd Mansoor Khan | Optical and Quantum Electronics

Performance Enhancement of Metasurface Grating Polarizer Using Deep Learning for Quantum Key Distribution Systems

2025-06-15

Hayder Aldahwi , Shelan K. Tawfeeq | Iraqi Journal of Laser

Metasurface polarizers are essential optical components in modern integrated optics and play a vital role in many optical applications including Quantum Key Distribution systems in quantum cryptography. However, inverse design … Metasurface polarizers are essential optical components in modern integrated optics and play a vital role in many optical applications including Quantum Key Distribution systems in quantum cryptography. However, inverse design of metasurface polarizers with high efficiency depends on the proper prediction of structural dimensions based on required optical response. Deep learning neural networks can efficiently help in the inverse design process, minimizing both time and simulation resources requirements, while better results can be achieved compared to traditional optimization methods. Hereby, utilizing the COMSOL Multiphysics Surrogate model and deep neural networks to design a metasurface grating structure with high extinction ration of »60000 at visible spectral wavelength of 632 nm, could be achieved.

TERABIT DATA RATE, OPTICAL SYSTEM DESIGN AND ANALYSIS FOR DIFFERENT COMPENSATION METHODS

2025-06-14

Ahmed Abdul Salam ALobaidi , Meena AlBaghdadi , A Al-Asadi +2 more | JOURNAL OF MECHANICS OF CONTINUA AND MATHEMATICAL SCIENCES

In recent times, several sectors and businesses have been doing extensive research on the use of Dense Wavelength Division Multiplexing (DWDM) and Radio Frequency Over Fiber (RFOF). These two technologies … In recent times, several sectors and businesses have been doing extensive research on the use of Dense Wavelength Division Multiplexing (DWDM) and Radio Frequency Over Fiber (RFOF). These two technologies are considered to be the most significant features. Increasing the data rate was a significant challenge that needed to be addressed, and the goal was to successfully implement a fiber optic system that was dependable and had a high number of associated channels. As a consequence of this, a 64-channel DWDM RFOF system that is capable of supporting a larger number of data rates of 2.56 Tbps has been designed and implemented in this study. A significant number of channels that have been sampled will be chosen for inquiry based on the characteristics of Quality Factor (QF) and Bit Error Rate (BER) that have been researched. This study will be carried out with the assistance of Optisystem software. These findings would be investigated at distances ranging from sixty to one hundred eighty kilometers, with the NRZ modulation format being used and a lunched power of zero decibels per meter. Additionally, the purpose of this study would be to explore the three distinct techniques of compensation, namely pre, post, and symmetrical, to quantify the individual performance of each approach on the suggested system. According to the findings, the use of symmetrical-based compensation yielded the most favorable outcomes, with the average QF acquired falling within the range of (20.33-14.09) dBm over distances ranging from (60-180) km. This demonstrates the dependability of the proposed system.

Beyond 60G SSB-FBMC signals transmission for Fiber-THz integrated system using simplified parallel Kramers-Kronig receiver

2025-06-14

Long Zhang , Jianjun Yu , Xiongwei Yang +7 more | Optics & Laser Technology

Unraveling reverse annealing: A study of D-wave quantum annealers

2025-06-12

NULL AUTHOR_ID | Physical review. A/Physical review, A

Towards Scalable and Accurate Property Prediction for Photonic Crystal Fibers with Federated Learning

2025-06-12

guanjun wang , Jianxun Liu , Shengchao Chen +1 more | Optics Express

UVL-Based Hybrid Neural Network Model for Generalized Optical Fiber Channel Modeling

2025-06-12

Jiaming Liu , Rui Wang , Hong Lin +4 more | Optics Express

Investigation into semiconductor optical amplifier (SOA) high quality four- wave mixing (FWM) wavelength conversion

2025-06-08

| ARPN Journal of Engineering and Applied Sciences

In this work, we have measured the signal-to-noise (SNR) ratio and Q-factors in a degenerate four-wave mixed (FWM) converted wavelength signal from a dual semiconductor optical amplifier (SOA) arrangement at … In this work, we have measured the signal-to-noise (SNR) ratio and Q-factors in a degenerate four-wave mixed (FWM) converted wavelength signal from a dual semiconductor optical amplifier (SOA) arrangement at different data rates, various SOA input powers, and changing converted wavelength spans. The results show that operating the functional SOA at optimum input power and increasing the saturation input power to the SOA pre-amp substantially improves the quality of the FWM signal. The optimum data rate to operate at was found to be around 600 Gb/s for a 4 nm down shift, with quality conversion still achieved at 1 Tb/s. Link length travel of around 280 km was shown to be possible for the FWM signal under the right conditions, with excellent receiver sensitivity shown. The modelled findings reported here should give practical designers an idea of how to optimize a converted FWM signal regarding trade-offs between SOA input power, gain, link length, data rate, and required conversion bandwidth.