Fiber-Optic Communication Systems

ISBN-13: 9781119737360 / Angielski / Twarda / 2021 / 544 str.

Govind P. Agrawal

Spis treści

Preface xvi1 Introduction 11.1 Historical Perspective 11.1.1 Need for Fiber-Optic Communications 21.1.2 Evolution of Lightwave Systems 41.2 Basic Concepts 81.2.1 Analog and Digital Signals 81.2.2 Channel Multiplexing 111.2.3 Modulation Formats 131.3 Optical Communication Systems 161.4 Lightwave System Components 181.4.1 Optical Fibers as a Communication Channel 181.4.2 Optical Transmitters 181.4.3 Optical Receivers 19Problems 20References 212 Optical Fibers 242.1 Geometrical-Optics Description 242.1.1 Step-Index Fibers 252.1.2 Graded-Index Fibers 272.2 Wave Propagation 292.2.1 Maxwell's Equations 292.2.2 Fiber Modes 312.2.3 Single-Mode Fibers 342.3 Dispersion in Single-Mode Fibers 372.3.1 Group-Velocity Dispersion 382.3.2 Material Dispersion 392.3.3 Waveguide Dispersion 402.3.4 Higher-Order Dispersion 412.3.5 Polarization-Mode Dispersion 432.4 Dispersion-Induced Limitations 442.4.1 Basic Propagation Equation 452.4.2 Chirped Gaussian Pulses 462.4.3 Limitations on the Bit Rate 492.5 Fiber Losses 522.5.1 Attenuation Coefficient 522.5.2 Material Absorption 532.5.3 Rayleigh Scattering 542.5.4 Waveguide Imperfections 552.6 Nonlinear Optical Effects 562.6.1 Stimulated Light Scattering 562.6.2 Nonlinear Phase Modulation 602.6.3 Four-Wave Mixing 632.7 Fiber Design and Fabrication 642.7.1 Silica Fibers 642.7.2 Plastic Optical Fibers 672.7.3 Cables and Connectors 69Problems 70References 723 Optical Transmitters 753.1 Semiconductor Laser Physics 753.1.1 Spontaneous and Stimulated Emissions 763.1.2 Nonradiative Recombination 773.1.3 Optical Gain 783.1.4 Feedback and Laser Threshold 803.1.5 Laser Structures and Modes 813.2 Single-Mode Semiconductor Lasers 833.2.1 Distributed Feedback Lasers 833.2.2 Coupled-Cavity Semiconductor Lasers 853.2.3 Tunable Semiconductor Lasers 863.2.4 Vertical-Cavity Surface-Emitting Lasers 883.3 Semiconductor Laser Characteristics 893.3.1 CW Characteristics 893.3.2 Modulation Bandwidth 923.3.3 Relative Intensity Noise 943.3.4 Spectral Linewidth 973.4 Modulation Techniques 983.4.1 Direct Modulation 993.4.2 External Modulation 1003.5 Light-Emitting Diodes 1033.5.1 LED Characteristics 1043.5.2 LED Structures 1063.6 Transmitter Design 1083.6.1 Source-Fiber Coupling 1083.6.2 Driving Circuitry 1103.6.3 Reliability and Packaging 111Problems 113References 1154 Optical Receivers 1194.1 Basic Concepts 1194.1.1 Responsivity and Quantum Efficiency 1194.1.2 Rise Time and Bandwidth 1214.2 Common Photodetectors 1224.2.1 p-n Photodiodes 1224.2.2 p-i-n Photodiodes 1244.2.3 Avalanche Photodiodes 1274.2.4 MSM Photodetectors 1334.3 Receiver Design 1354.3.1 The Front End 1354.3.2 The Linear Channel 1374.3.3 Data-Recovery Section 1384.3.4 Integrated Receivers 1394.4 Receiver Noise 1414.4.1 Noise Mechanisms 1414.4.2 SNR of p-i-n Receivers 1434.4.3 SNR of APD Receivers 1444.5 Coherent Detection 1484.5.1 Local Oscillator 1484.5.2 Homodyne Detection 1494.5.3 Heterodyne Detection 1504.5.4 Signal-to-Noise Ratio 1504.6 Receiver Sensitivity 1514.6.1 Bit-Error Rate 1514.6.2 Minimum Received Power 1544.6.3 Quantum Limit of Photodetection 1564.7 Sensitivity Degradation 1574.7.1 Extinction Ratio 1574.7.2 Intensity Noise 1584.7.3 Timing Jitter 1604.8 Receiver Performance 162Problems 164References 1665 Lightwave Systems 1705.1 System Architectures 1705.1.1 Point-to-Point Links 1705.1.2 Distribution Networks 1725.1.3 Local-Area Networks 1735.2 Design Guidelines 1755.2.1 Loss-Limited Lightwave Systems 1755.2.2 Dispersion-Limited Lightwave Systems 1765.2.3 Power Budget 1775.2.4 Rise-Time Budget 1795.3 Long-Haul Systems 1815.3.1 Performance-Limiting Factors 1815.3.2 Terrestrial Lightwave Systems 1835.3.3 Undersea Lightwave Systems 1865.4 Sources of Power Penalty 1885.4.1 Modal Noise 1885.4.2 Mode-Partition Noise 1905.4.3 Reflection Feedback and Noise 1915.4.4 Dispersive Pulse Broadening 1945.4.5 Frequency Chirping 1955.4.6 Eye-Closure Penalty 1975.5 Forward Error Correction 1985.5.1 Error-Correcting Codes 1985.5.2 Coding Gain 1995.6 Computer-Aided Design 200Problems 202References 2046 Multichannel Systems 2086.1 WDM Systems and Networks 2086.1.1 High-Capacity Point-to-Point Links 2096.1.2 Wide-Area and Metro-Area Networks 2126.1.3 Multiple-Access WDM Networks 2156.2 WDM Components 2166.2.1 Optical Filters 2176.2.2 Multiplexers and Demultiplexers 2226.2.3 Add-Drop Multiplexers 2246.2.4 Star Couplers 2276.2.5 Wavelength Routers 2286.2.6 WDM Transmitters and Receivers 2306.3 System Performance Issues 2336.3.1 Linear Crosstalk 2336.3.2 Raman-Induced Nonlinear Crosstalk 2356.3.3 XPM-Induced Nonlinear Crosstalk 2376.3.4 FWM-Induced Nonlinear Crosstalk 2396.3.5 Other Design Issues 2406.4 Time-Division Multiplexing 2416.4.1 Time-Domain Multiplexing 2426.4.2 Time-Domain Demultiplexing 2436.4.3 Performance of OTDM Systems 2456.5 Subcarrier Multiplexing 2466.5.1 Analog and Digital SCM Systems 2466.5.2 Orthogonal Frequency-Division multiplexing 2486.6 Code-Division Multiplexing 2506.6.1 Time-Domain Encoding 2516.6.2 Frequency-Domain Encoding 253Problems 255References 2577 Loss Management 2647.1 Compensation of Fiber Losses 2647.1.1 Periodic Amplification Scheme 2657.1.2 Lumped Versus Distributed Amplification 2677.1.3 Bidirectional Pumping Scheme 2687.2 Erbium-Doped Fiber Amplifiers 2697.2.1 Pumping and Gain Spectrum 2697.2.2 Two-Level Model 2707.2.3 Amplifier Noise 2737.2.4 Multichannel Amplification 2757.3 Raman Amplifiers 2777.3.1 Raman Gain and Bandwidth 2787.3.2 Raman-Induced Signal Gain 2797.3.3 Multiple-Pump Raman Amplification 2817.3.4 Noise Figure of Raman Amplifiers 2837.4 Optical Signal-To-Noise Ratio 2857.4.1 Lumped Amplification 2857.4.2 Distributed Amplification 2877.5 Electrical Signal-To-Noise Ratio 2887.5.1 ASE-Induced Current Fluctuations 2887.5.2 Impact of ASE on SNR 2907.5.3 Noise Buildup in an Amplifier Chain 2917.6 Receiver Sensitivity and Q Factor 2927.6.1 Bit-Error Rate 2927.6.2 Relation between Q Factor and Optical SNR 2947.7 Role of Dispersive and Nonlinear Effects 2957.7.1 Noise Growth through Modulation Instability 2957.7.2 Noise-Induced Signal Degradation 2977.7.3 Noise-Induced Energy Fluctuations 2997.7.4 Noise-Induced Timing Jitter 3007.8 Periodically Amplified Lightwave Systems 3007.8.1 Numerical Approach 3017.8.2 Optimum Launched Power 304Problems 306References 3078 Dispersion Management 3108.1 Dispersion Problem and Its Solution 3108.2 Dispersion-Compensating Fibers 3128.2.1 Conditions for Dispersion Compensation 3128.2.2 Dispersion Maps 3138.2.3 DCF Designs 3158.3 Fiber Bragg Gratings 3178.3.1 Constant-Period Gratings 3188.3.2 Chirped Fiber Gratings 3208.3.3 Sampled Gratings 3228.4 Dispersion-Equalizing Filters 3258.4.1 Gires-Tournois Filters 3258.4.2 Mach-Zehnder and Other Filters 3278.5 Optical Phase Conjugation 3298.5.1 Principle of Operation 3308.5.2 Compensation of Self-Phase Modulation 3318.5.3 Generation of Phase-Conjugated Signal 3328.6 Advanced Techniques 3358.6.1 Tunable Dispersion Compensation 3358.6.2 Higher-Order Dispersion Management 3388.6.3 PMD Compensation 3408.7 Electronic Dispersion Compensation 3438.7.1 Pre-compensation at the Transmitter 3438.7.2 Post-Compensation at the Receiver 347Problems 349References 3519 Control of Nonlinear Effects 3559.1 Impact of Fiber Nonlinearity 3559.1.1 System Design Issues 3569.1.2 Semianalytic Approach 3599.1.3 Soliton and Pseudo-linear Regimes 3619.2 Solitons in Optical Fibers 3639.2.1 Properties of Optical Solitons 3649.2.2 Loss-Managed Solitons 3679.2.3 Dispersion-Managed Solitons 3709.2.4 Timing Jitter 3749.3 Pseudo-linear Lightwave Systems 3789.3.1 Origin of Intrachannel Nonlinear Effects 3789.3.2 Intrachannel Cross-Phase Modulation 3809.3.3 Intrachannel Four-Wave Mixing 3849.4 Management of Nonlinear Effects 3879.4.1 Optimization of Dispersion Maps 3879.4.2 Phase-Alternation Technique 3909.4.3 Polarization Bit Interleaving 3929.4.4 Optical Phase Conjugation 3939.4.5 Phase-Sensitive Amplification 395Problems 396References 39810 Coherent Lightwave Systems 40210.1 Coherent Transmitters 40310.1.1 Encoding of Optical Signals 40310.1.2 Amplitude and Phase Modulators 40510.1.3 Quadrature modulator 40610.2 Coherent Receivers 40810.2.1 Synchronous Heterodyne Demodulation 40810.2.2 Asynchronous Heterodyne Demodulation 41010.2.3 Optical Delay Demodulation 41110.2.4 Phase Diversity and Polarization Diversity 41310.3 Noise and Bit-Error Rate 41510.3.1 Synchronous Heterodyne Receivers 41510.3.2 Asynchronous Heterodyne Receivers 41810.3.3 Receivers with Optical Delay Demodulation 41910.4 Sources of Performance Degradation 42110.4.1 Intensity Noise of Lasers 42110.4.2 Phase Noise of Lasers 42210.4.3 Effects of Fiber's Dispersion 42410.5 Management of Nonlinear Effects 42510.5.1 Nonlinear Phase Noise 42610.5.2 Compensation of Nonlinear Phase Noise 42910.5.3 Nonlinear Interference Noise 43210.6 Digital Signal Processing 43510.6.1 Removal of Intermediate Frequency and Phase fluctuations 43510.6.2 Compensation of GVD and PMD 43710.6.3 Digital Backward Propagation 44010.7 Experimental Progress 44210.7.1 DPSK and DQPSK formats 44210.7.2 QPSK and QAM formats 44510.7.3 Coherent Orthogonal FDM 44810.7.4 Optical Superchannels 45010.8 Channel Capacity 452Problems 454References 45511 Space-Division Multiplexing 46211.1 SDM Technique 46211.2 Modes of Optical Fibers 46411.2.1 Step-Index Fibers 46411.2.2 Graded-Index Fibers 46711.2.3 Multicore Fibers 46911.3 SDM Components 47111.3.1 Design of SDM Fibers 47111.3.2 Spatial Multiplexers and Demultiplexers 47411.3.3 Multicore/Multimode Fiber Amplifiers 47911.3.4 Other SDM Components 48111.4 Modeling of SDM Systems 48211.4.1 Multimode Coupled Nonlinear Equations 48311.4.2 Averaged Multimode Nonlinear Equations 48611.4.3 Nonlinear Effects in MCFs 48811.4.4 Nonlinear Effects in MMFs 49111.5 Experimental Progress 49411.5.1 MCF-Based SDM Systems 49411.5.2 MMF-Based SDM Systems 49611.5.3 High-Capacity SDM Systems 498Problems 499References 50012 Advanced Topics 50512.1 Optical Signal Processing 50612.1.1 Nonlinear Optical Loop Mirrors 50612.1.2 Parametric Amplifiers 51012.1.3 Semiconductor Optical Amplifiers 51312.1.4 Bistable Optical Devices 51612.1.5 Optical Flip-Flops 51812.2 Wavelength Conversion 52212.2.1 XPM-Based Wavelength Converters 52212.2.2 FWM-Based Wavelength Converters 52512.2.3 Semiconductor Waveguides 52812.2.4 SOA-Based Wavelength Converters 53012.3 Ultrafast Optical Switching 53212.3.1 Time-Domain Demultiplexing 53212.3.2 Packet Switching 53612.3.3 Format Conversion 53812.4 Optical Regeneration 54012.4.1 2R Regenerators 54112.4.2 3R Regenerators 54512.4.3 Regeneration of Phase-Encoded Signals 54912.5 Nonlinear Frequency-Division Multiplexing 55212.5.1 Nonlinear Fourier Transform 55212.5.2 Practical Implementation 554Problems 556References 557A System of Units 566B Acronyms 568C Formula for Pulse Broadening 572D Nyquist Pulses 574References 575Index 576

O autorze

Govind P. Agrawal, PhD, is James C. Wyant Professor at the Institute of Optics at the University of Rochester. He is a Fellow of the Optical Society of America and the IEEE. He is also a Senior Scientist at the Laboratory for Laser Energetics and has authored or co-authored over 400 research papers, book chapters, and monographs.