Lightwave Technology

GOVIND P. AGRAWAL, PhD, is a Professor of Optics at The Institute of Optics, University of Rochester, New York, and a Fellow of the Optical Society of America and the IEEE. Internationally recognized as an expert in his field, Dr. Agrawal has authored or coauthored more than 300 research papers, books, and monographs.

• Preface1 Introduction 11.1 Evolution of Lightwave Systems 11.2 Components of a Lightwave System 71.2.1 Optical Transmitters 71.2.2 Communication Channel 81.2.3 Optical Receivers 91.3 Electrical Signals 111.3.1 Analog and Digital Signals 111.3.2 Advantages of Digital Format 121.3.3 Analog to Digital Conversion 131.4 Channel Multiplexing 161.4.1 Time-Division Multiplexing 161.4.2 Frequency-Division Multiplexing 181.4.3 Code-Division Multiplexing 20Problems 21References 222 Optical Signal Generation 262.1 Modulation Formats 262.1.1 ASK Format 282.1.2 PSK Format 302.1.3 FSK Format 312.2 Digital Data Formats 322.2.1 Nonreturn-to-Zero Format 332.2.2 Return-to-Zero Format 342.2.3 Power Spectral Density 342.3 Bit-Stream Generation 372.3.1 NRZ Transmitters 372.3.2 RZ Transmitters 382.3.3 Modified RZ Transmitters 402.3.4 DPSK Transmitters and Receivers 462.4 Transmitter Design 472.4.1 Coupling Losses and Output Stability 482.4.2 Wavelength Stability and Tunability 502.4.3 Monolithic Integration 532.4.4 Reliability and Packaging 55Problems 57References 583 Signal Propagation in Fibers 633.1 Basic Propagation Equation 633.2 Impact of Fiber Losses 673.2.1 Loss Compensation 673.2.2 Lumped and Distributed Amplification 693.3 Impact of Fiber Dispersion 713.3.1 Chirped Gaussian Pulses 713.3.2 Pulses of Arbitrary Shape 743.3.3 Effects of Source Spectrum 763.3.4 Limitations on the Bit Rate 783.3.5 Dispersion compensation 813.4 Polarization-Mode Dispersion 823.4.1 Fibers with Constant Birefringence 833.4.2 Fibers with Random Birefringence 843.4.3 Jones-Matrix Formalism 873.4.4 Stokes-Space Description 893.4.5 Statistics of PMD 923.4.6 PMD-Induced Pulse Broadening 953.4.7 Higher-Order PMD Effects 963.5 Polarization-Dependent Losses 983.5.1 PDL Vector and Its Statistics 993.5.2 PDL-lnduced Pulse Distortion 101Problems 103References 1044 Nonlinear Impairments 1074.1 Self-Phase Modulation 1074.1.1 Nonlinear Phase Shift 1084.1.2 Spectral Broadening and Narrowing 1114.1.3 Effects of Fiber Dispersion 1134.1.4 Modulation Instability 1144.2 Cross-Phase Modulation 1174.2.1 XPM-Induced Phase Shift 1174.2.2 Effects of Group-Velocity Mismatch 1194.2.3 Effects of Group-Velocity Dispersion 1214.2.4 Control of XPM Interaction 1244.3 Four-Wave Mixing 1254.3.1 FWM Efficiency 1264.3.2 Control of FWM 1284.4 Stimulated Raman Scattering 1304.4.1 Raman-Gain Spectrum 1314.4.2 Raman Threshold 1324.5 Stimulated Brillouin Scattering 1344.5.1 Brillouin Threshold 1344.5.2 Control of SBS 1364.6 Nonlinear Pulse Propagation 1374.6.1 Moment Method 1374.6.2 Variational Method 1394.6.3 Specific Analytic Solutions 1404.7 Polarization Effects 1424.7.1 Vector NLS equation 1424.7.2 Manakov Equation 144Problems 145References 1465 Signal Recovery and Noise 1515.1 Noise Sources 1515.1.1 Shot Noise 1525.1.2 Thermal Noise 1535.2 Signal-to-Noise Ratio 1545.2.1 Receivers with a p-i-n Photodiode 1555.2.2 APD Receivers 1565.3 Receiver Sensitivity 1595.3.1 Bit-Error Rate 1605.3.2 Minimum Average Power 1635.3.3 Quantum Limit of Photodetection 1655.4 Sensitivity Degradation 1665.4.1 Finite Extinction Ratio 1665.4.2 Intensity Noise of Lasers 1685.4.3 Dispersive Pulse Broadening 1705.4.4 Frequency Chirping 1715.4.5 Timing Jitter 1725.4.6 Eye-Closure Penalty 1755.5 Forward Error Correction 1765.5.1 Error-Correcting Codes 1775.5.2 Coding Gain 1775.5.3 Optimum Coding Overhead 178Problems 181References 1826 Optical Amplifier Noise 1856.1 Origin of Amplifier Noise 1856.1.1 EDFA Noise 1866.1.2 Distributed Amplification 1896.2 Optical SNR 1906.2.1 Lumped Amplification 1906.2.2 Distributed Amplification 19i6.3 Electrical SNR 1936.3.1 ASE-Induced Current Fluctuations 1936.3.2 Impact of ASE on SNR 1946.3.3 Noise Figure of Distributed Amplifiers 1966.3.4 Noise Buildup in an Amplifier Chain 1986.4 Receiver Sensitivity and Q Factor 1996.4.1 Bit-Error Rate 1996.4.2 Non-Gaussian Receiver Noise 2016.4.3 Relation between Q Factor and Optical SNR 2026.5 Role of Dispersive and Nonlinear Effects 2046.5.1 Noise Growth through Modulation Instability 2046.5.2 Noise-Induced Signal Degradation 2076.5.3 Noise-Induced Energy Fluctuations 2106.5.4 Noise-Induced Frequency Fluctuations 2116.5.5 Noise-Induced Timing Jitter 2136.5.6 Jitter Reduction through Distributed Amplification 2146.6 Periodically Amplified Lightwave Systems 2166.6.1 Numerical Approach 2166.6.2 Optimum Launched Power 219Problems 221References 2227 Dispersion Management 2257.1 Dispersion Problem and Its Solution 2257.2 Dispersion-Compensating Fibers 2277.2.1 Conditions for Dispersion Compensation 2287.2.2 Dispersion Maps 2297.2.3 DCF Designs 2317.2.4 Reverse-Dispersion Fibers 2347.3 Dispersion-Equalizing Filters 2357.3.1 Gires-Toumois Filters 2357.3.2 Mac h-Zehnder Filters 2377.3.3 Other All-Pass Filters 2397.4 Fiber Bragg Gratings 2407.4.1 Constant-Period Gratings 2407.4.2 Chirped Fiber Gratings 2437.4.3 Sampled Gratings 2467.5 Optical Phase Conjugation 2507.5.1 Principle of Operation 2507.5.2 Compensation of Self-Phase Modulation 2507.5.3 Generation of Phase-Conjugated Signal 2537.6 Other Schemes 2567.6.1 Prechirp Technique 2567.6.2 Novel Coding Techniques 2597.6.3 Nonlinear Prechirp Techniques 2607.6.4 Electronic Compensation Techniques 2617.7 High-Speed Lightwave Systems 2627.7.1 Tunable Dispersion Compensation 2627.7.2 Higher-Order Dispersion Management 2677.7.3 PMD Compensation 270Problems 274References 2768 Nonlinearity Management 2848.1 Role of Fiber Nonlinearity 2848.1.1 System Design Issues 2858.1.2 Semianalytic Approach 2898.1.3 Soliton and Pseudo-linear Regimes 2918.2 Solitons in Optical Fibers 2938.2.1 Properties of Optical Solitons 2938.2.2 Loss-Managed Solitons 2978.3 Dispersion-Managed Solitons 3018.3.1 Dispersion-Decreasing Fibers 3018.3.2 Periodic Dispersion Maps 3028.3.3 Design Issues 3058.3.4 Timing Jitter 3088.3.5 Control of Timing Jitter 3108.4 Pseudo-linear Lightwave Systems 3148.4.1 Intrachannel Nonlinear Effects 3148.4.2 Intrachannel XPM 3168.4.3 Intrachannel FWM 3208.5 Control of Intrachannel Nonlinear Effects 3248.5.1 Optimization of Dispersion Maps 3248.5.2 Phase-A Item at ion Techniques 3288.5.3 Polarization Bit Interleaving 3308.6 High-Speed Lightwave Systems 3328.6.1 OTDM Transmitters and Receivers 3328.6.2 Performance of OTDM System 335Problems 337References 3399 WDM Systems 3469.1 Basic WDM Scheme 3469.1.1 System Capacity and Spectral Efficiency 3479.1.2 Bandwidth and Capacity of WDM Systems 3489.2 Linear Degradation Mechanisms 3519.2.1 Out-of-Band Linear Crosstalk 3519.2.2 In-Band Linear Crosstalk 3539.2.3 Filter-Induced Signal Distortion 3569.3 Nonlinear Crosstalk 3579.3.1 Raman Crosstalk 3589.3.2 Four-Wave Mixing 3639.4 Cross-Phase Modulation 3669.4.1 Amplitude Fluctuations 3669.4.2 Timing Jitter 3699.5 Control of Nonlinear Effects 3749.5.1 Optimization of Dispersion Maps 3749.5.2 Use of Raman Amplification 3789.5.3 Polarization Interleaving of Channels 3819.5.4 Use of DPSK Formal 3839.6 Major Design Issues 3859.6.1 Spectral Efficiency 3869.6.2 Dispersion Fluctuations 3919.6.3 PMD and Polarization-Dependent Losses 3939.6.4 Wavelength Stability and Other Issues 395Problems 397References 39810 Optical Networks 40410.1 Network Architecture and Topologies 40410.1.1 Wide-Area Networks 40410.1.2 Metropolitan-Area Networks 40610.1.3 Local-Area Networks 40710.2 Network Protocols and Layers 40910.24 Evolution of Protocols 40910.2.2 Evolution of WDM Networks 41010.2.3 Network Planes 41210.3 Wavelength-Routing Networks 41310.34 Wavelength Switching and Its Limitations 41410.3.2 Architecture of Optical Cross-Connects 41410.3.3 Switching Technologies for Cross-Connects 41710.4 Packet-Switched Networks 41810.44 Optical Label Swapping 41910.4.2 Techniques for Label Coding 42010.4.3 Contention Resolution 42410.5 Other Routing Techniques 42510.54 Optical Burst Switching 42610.5.2 Photonic Slot Routing 42710.5.3 High-Speed TDM Networks 42910.6 Distribution and Access Networks 43110.64 Broadcast-and-Select Networks 43110.6.2 Passive Optical Networks 433Problems 436References 437Appendix A System of Units 442Appendix B Software Package 444Appendix C Acronyms 446Index 449