Fiber Optic Measurement Techniques

This book is an indispensable collection of key optical measurement techniques essential for developing and characterizing today's photonic devices and fiber optic systems. Provided are comprehensive and systematic descriptions of various fiber optic measurement methods with the emphasis on the understanding of optoelectronic signal processing methodologies, helping the reader to weigh up the pros and cons of each technique and establish their suitability for the task at hand. Cover Page ......Page 1 Copyright......Page 2 Dedication......Page 3 Preface......Page 4 Acknowledgements......Page 5 About the Author......Page 7 Constants......Page 8 Fundamentals of Optical Devices......Page 9 Introduction......Page 10 Laser Diodes and LEDs......Page 12 Pn Junction and Energy Diagram......Page 13 Direct and Indirect Semiconductors......Page 14 Carrier Confinement......Page 15 Spontaneous Emission and Stimulated Emission......Page 16 Light-Emitting Diodes (LEDs)......Page 17 PI Curve......Page 18 Modulation Dynamics......Page 20 Laser Diodes (LDs)......Page 21 Rate Equations......Page 24 Threshold Current Density......Page 26 PJ Relationship About Threshold......Page 27 Mode Suppression Ratio (MSR)......Page 28 Turn-on Delay......Page 30 Small-Signal Modulation Response......Page 31 Phase Noise......Page 33 Single-Frequency Semiconductor Lasers......Page 34 DFB Laser Diode......Page 35 External Cavity Laser Diode......Page 36 Pn-Junction Photodiodes......Page 40 Responsivity and Bandwidth......Page 42 Electrical Characteristics of a Photodiode......Page 44 Photodetector Noise and SNR......Page 45 Noise-Equivalent Power (NEP)......Page 48 Avalanche Photodiodes (APDs)......Page 49 Reflection and Refraction......Page 52 Fresnel Reflection Coefficients......Page 53 Normal Incidence......Page 55 Optical Field Phase Shift Between the Incident and the Reflected Beams......Page 56 Propagation Modes in Optical Fibers......Page 57 Geometric Optics Analysis......Page 59 Mode Analysis Using Electromagnetic Field Theory......Page 62 Numerical Aperture......Page 66 Optical Fiber Attenuation......Page 70 Phase Velocity and Group Velocity......Page 75 Group Velocity Dispersion......Page 77 Sources of Chromatic Dispersion......Page 78 Modal Dispersion......Page 81 Polarization Mode Dispersion (PMD)......Page 82 Stimulated Brillouin Scattering......Page 85 Stimulated Raman Scattering......Page 86 Kerr Effect Nonlinearity and Nonlinear Schrödinger Equation......Page 87 Optical Amplifiers......Page 93 Optical Gain, Gain Bandwidth, and Saturation......Page 94 Steady-State Analysis......Page 97 Gain Dynamics of OSA......Page 99 Optical Wavelength Conversion Using Cross-Gain Saturation......Page 103 Wavelength Conversion Using FWM in SOA......Page 104 Optical Phase Modulation in an SOA......Page 107 Erbium-Doped Fiber Amplifiers (EDFAs)......Page 108 Absorption and Emission Cross-Sections......Page 110 Rate Equations......Page 112 Forward Pumping and Backward Pumping......Page 118 EDFAs with AGC and APC......Page 119 EDFA Gain Flattening......Page 122 External Electro-Optic Modulator......Page 123 Basic Operation Principle of Electro-Optic Modulators......Page 124 Frequency Doubling and Duo-Binary Modulation......Page 129 Optical Single-Side Modulation......Page 131 Optical Modulators Using Electro-Absorption Effect......Page 133 References ......Page 135 Basic Instrumentation for Optical Measurement......Page 137 Introduction......Page 138 General Specifications......Page 139 Fundamentals of Diffraction Gratings......Page 142 Measure the Diffraction Angle Spreading Whenthe Input Only has a Single Frequency......Page 144 Sweep the Signal Wavelength While Measuringthe Output at a Fixed Diffraction Angle......Page 145 Basic OSA Configurations......Page 146 Basic FPI Configuration and Transfer Function......Page 154 Free Spectral Range (FSR)......Page 158 Contrast......Page 159 Scanning FPI Spectrum Analyzer......Page 161 Scanning FPI Basic Optical Configurations......Page 165 Optical Spectrum Analyzer Using the Combination of Grating and FPI......Page 167 Mach-Zehnder Interferometers......Page 168 Michelson Interferometers......Page 176 Operating Principle of a Michelson Interferometer......Page 177 Measurement and Characterization of Michelson Interferometers......Page 180 Techniques to Increase Frequency Selectivity......Page 182 Optical Wavelength Meter......Page 187 Operating Principle of a Wavelength Meter Based on Michelson Interferometer......Page 188 Wavelength Coverage......Page 191 Spectral Resolution......Page 192 Wavelength Calibration......Page 193 Wavelength Meter Based on Fizeau Wedge Interferometer......Page 194 General Description of Lightwave Polarization......Page 196 The Stokes Parameters and the Poincare Sphere......Page 198 Optical Polarimeters......Page 201 Operating Principle......Page 204 Heterodyne and Homodyne Detection......Page 207 Signal-to-Noise-Ratio in Coherent Detection Receivers......Page 209 Balanced Coherent Detection and Polarization Diversity......Page 210 Phase Diversity in Coherent Homodyne Detection......Page 212 Coherent OSA Based on Swept Frequency Laser......Page 215 Waveform Measurement......Page 219 Oscilloscope Operating Principle......Page 220 Digital Sampling Oscilloscopes......Page 224 High-Speed Sampling of Optical Signal......Page 227 Nonlinear Optical Sampling......Page 228 Linear Optical Sampling......Page 229 High-Speed Electric ADC Using Optical Techniques......Page 231 Optical Low-Coherence Reflectometry......Page 240 Fourier-Domain Reflectometry......Page 248 S-Parameters and RF Network Analyzer......Page 254 Optical Network Analyzers......Page 257 Scalar Optical Network Analyzer......Page 258 Vector Optical Network Analyzer......Page 259 References......Page 264 Characterization of Optical Devices......Page 267 Characterization of RIN and Linewidth of Semiconductor Lasers......Page 268 Measurement of Relative Intensity Noise (RIN)......Page 269 Measurement of Laser Phase Noise and Linewidth......Page 274 Coherent Detection......Page 277 Self-homodyne detection......Page 280 Measurement of Electro-Optic Modulation Response......Page 284 Frequency-Domain Characterization......Page 285 Time-Domain Characterization......Page 289 Measurement of Frequency Chirp......Page 290 Modulation Spectral Measurement......Page 291 Measurement Utilizing Fiber Dispersion......Page 293 Time-Domain Measurement of Modulation-Induced Chirp......Page 300 Wideband Characterization of an Optical Receiver......Page 304 Characterization of Photodetector Responsivity and Linearity......Page 305 Frequency Domain Characterization of Photodetector Response......Page 307 Photodetector Bandwidth Characterization Using Source Spontaneous-Spontaneous Beat Noise......Page 309 Photodetector Characterization Using Short Optical Pulses......Page 312 Measurement of Amplifier Optical Gain......Page 314 Dynamic Gain Tilt......Page 319 Optical Amplifier Noise......Page 322 Optical Domain Characterization of ASE Noise......Page 324 Impact of ASE Noise in Electrical Domain......Page 326 Signal-Spontaneous Emission Beat Noise......Page 327 Spontaneous-Spontaneous Beat Noise Spectral Density......Page 329 Noise Figure Definition......Page 331 Electrical Domain Characterization of a Noise Figure......Page 333 Time-Domain Characteristics of EDFA......Page 335 Characterization of Passive Optical Components......Page 337 Fiber-Optic Couplers......Page 338 Fiber Bragg Grating Filters......Page 343 Thin Film-Based Interference Filters......Page 348 Arrayed Waveguide Gratings......Page 351 Characterization of Optical Filter Transfer Functions......Page 353 Modulation Phase-Shift Technique......Page 354 Interferometer Technique......Page 358 Optical Isolators......Page 361 Optical Circulators......Page 364 Reference......Page 369 Optical Fiber Measurement......Page 372 Introduction......Page 373 Standard Optical Fibers for Transmission......Page 374 Specialty Optical Fibers......Page 377 Measurement of Fiber Mode-Field Distribution......Page 381 Near-Field, Far-Field, and Mode-Field Diameter......Page 382 Far-Field Measurement Techniques......Page 385 Near-Field Measurement Techniques......Page 387 Cutback Technique......Page 389 Optical Time-Domain Reflectometers......Page 391 Improvement Considerations of OTDR......Page 398 Fiber Dispersion Measurements......Page 401 Intermodal Dispersion and Its Measurement......Page 402 Pulse Distortion Method......Page 403 Frequency Domain Measurement......Page 405 Modulation Phase Shift Method......Page 407 Baseband AM Response Method......Page 410 Interferometric Method......Page 412 Representation of Fiber Birefringence and PMD Parameter......Page 416 Pulse Delay Method......Page 420 The Interferometric Method......Page 422 Poincare Arc Method......Page 425 Fixed Analyzer Method......Page 427 The Jones Matrix Method......Page 431 The Mueller Matrix Method......Page 438 Determination of Polarization-Dependent Loss......Page 445 PMD Sources and Emulators......Page 449 Measurement of Fiber Nonlinearity......Page 453 Measurement of Stimulated Brillouin Scattering Coefficient......Page 454 Measurement of the Stimulated Raman Scattering Coefficient......Page 460 Measurement of Kerr effect nonlinearity......Page 466 Nonlinear Index Measurement Using SPM......Page 467 Nonlinear Index Measurement Using FWM......Page 470 Nonlinear Index Measurement Using Cross-Phase Modulation......Page 475 Nonlinear Index Measurement Using Modulation Instability......Page 480 Optical System Performance Measurements......Page 487 Introduction......Page 488 Overview of Fiber-Optic Transmission Systems......Page 489 Optical System Performance Considerations......Page 490 Receiver BER and Q......Page 492 System Q Estimation Based on Eye Diagram Parameterization......Page 500 Bit Error Rate Testing......Page 505 Pattern Generator......Page 507 Error Detection......Page 510 Receiver Sensitivity Measurement and OSNR Tolerance......Page 514 Receiver Sensitivity and Power Margin......Page 515 OSNR Margin and Required OSNR (R-OSNR)......Page 520 BER vs. Decision Threshold Measurement......Page 527 Waveform Distortion Measurements......Page 530 Basic Jitter Parameters and Definitions......Page 533 Jitter Measurement Based on Sampling Oscilloscope......Page 538 Jitter Measurement Based on a Phase Detector......Page 540 Jitter Measurement Based on a BER-T Scan......Page 541 In Situ Monitoring of Chromatic Dispersion......Page 543 Basic Operating Principle......Page 547 PMD Monitoring Using Coherent Detection......Page 549 Difference Between Fiber DGD and the DGD Experienced by an Optical Signal......Page 553 In Situ PDL Monitoring......Page 557 XPM-Induced Intensity Modulation in IMDD Optical Systems......Page 562 XPM-Induced Phase Modulation......Page 578 FWM-Induced Crosstalk in IMDD Optical Systems......Page 581 Characterization of Raman Crosstalk with Wide Channel Separation......Page 587 Modulation-Instability and Transfer Matrix Formulation......Page 596 Power Spectrum of The Optical Field......Page 599 Noise Description at a Direct-detection Optical Receiver......Page 601 Effect of Dispersion Compensation......Page 604 Impact of Modulation Instability in Amplified Multispan Fiber Systems......Page 606 Characterization of Modulation Instability in Fiber-Optic Systems......Page 607 Optical System Performance Evaluation Based on Required OSNR......Page 612 Measurement of R-SNR Due to Chromatic Dispersion......Page 613 Measurement of R-SNR Due to Fiber Nonlinearity......Page 616 Measurement of R-OSNR Due to Optical Filter Misalignment......Page 621 Fiber-Optic Recirculating Loop......Page 622 Operation Principle of a Recirculating Loop......Page 623 Measurement Procedure and Time Control......Page 624 Optical Gain Adjustment in the Loop......Page 628 Reference......Page 634 Fiber Optic Measurement Techniques is an indispensable collection of key optical measurement techniques essential for developing and characterizing today’s photonic devices and fiber optic systems. The book gives comprehensive and systematic descriptions of various fiber optic measurement methods with the emphasis on the understanding of optoelectronic signal processing methodologies, helping the reader to weigh up the pros and cons of each technique and establish their suitability for the task at hand.

Carefully balancing descriptions of principle, operations and optoelectronic circuit implementation, this indispensable resource will enable the engineer to:

• Understand the implications of various measurement results and system performance qualifications
• Characterize modern optical systems and devices
• Select optical devices and subsystems in optical network design and implementation
• Design innovative instrumentations for fiber optic systems

This book brings together in one volume the fundamental principles with the latest techniques, making it a complete resource for the optical and communications engineer developing future optical devices and fiber optic systems.

"Optical fiber communication systems and networks constitute the core of the telecom infrastructure of the information society worldwide. Accurate knowledge of the properties of the contituent components, and of the performance of the subsystems and systems must be obtained in order to ensure reliable transmission, distribution, and delivery of information. This book is an authoritative and comprehensive treatment of fiber-optic measurement techniques, including not only fundamental principles and methodologies but also various instrumentations and practical implementations. It is an excellent up-to-date resource and reference for the academic and industrial researcher as well as the field engineer in manufacturing and network operations." – Dr. Tingye Li, AT&T Labs (retired)

Rongqing Hui received his PhD in Electrical Engineering from Politecnico di Torino, Italy in 1993. He is currently a tenured professor in the department of Electrical Engineering and Computer Science at the University of Kansas. He has published more than 90 refereed technical papers in the area of fiber-optic communications and holds 13 patents. Dr. Hui currently serves as an Associate Editor of IEEE Transactions on Communications.

Maurice O'Sullivan has worked for Nortel for a score of years, at first in the optical cable business, developing factory-tailored metrology for optical fiber, but, in the main, in the optical transmission business developing, modeling and verifying physical layer designs & performance of Nortel's line and highest rate transmission product including OC-192, MOR, MOR+, LH1600G, eDCO and eDC40G. He holds a Ph.D. in physics (high resolution spectroscopy) from the University of Toronto, is a Nortel Fellow and has been granted more than 30 patents.

* The only book to combine explanations of the basic principles with latest techniques to enable the engineer to develop photonic systems of the future
* Careful and systematic presentation of measurement methods to help engineers to choose the most appropriate for their application
* The latest methods covered, such as real-time optical monitoring and phase coded systems and subsystems, making this the most up-to-date guide to fiber optic measurement on the market Fiber Optic Measurement Techniques is an indispensable collection of key optical measurement techniques essential for developing and characterizing today{u2019}s photonic devices and fiber optic systems. The book gives comprehensive and systematic descriptions of various fiber optic measurement methods with the emphasis on the understanding of optoelectronic signal processing methodologies, helping the reader to weigh up the pros and cons of each technique and establish their suitability for the task at hand. Carefully balancing descriptions of principle, operations and optoelectronic circuit implementation, this indispensable resource will enable the engineer to: {u2022} Understand the implications of various measurement results and system performance qualifications {u2022} Characterize modern optical systems and devices {u2022} Select optical devices and subsystems in optical network design and implementation {u2022} Design innovative instrumentations for fiber optic systems This book brings together in one volume the fundamental principles with the latest techniques, making it a complete resource for the optical and communications engineer developing future optical devices and fiber optic systems. "Optical fiber communication systems and networks constitute the core of the telecom infrastructure of the information society worldwide. Accurate knowledge of the properties of the contituent components, and of the performance of the subsystems and systems must be obtained in order to ensure reliable transmission, distribution, and delivery of information. This book is an authoritative and comprehensive treatment of fiber-optic measurement techniques, including not only fundamental principles and methodologies but also various instrumentations and practical implementations. It is an excellent up-to-date resource and reference for the academic and industrial researcher as well as the field engineer in manufacturing and network operations." {u2013} Dr. Tingye Li, AT&T Labs (retired) Rongqing Hui received his PhD in Electrical Engineering from Politecnico di Torino, Italy in 1993. He is currently a tenured professor in the department of Electrical Engineering and Computer Science at the University of Kansas. He has published more than 90 refereed technical papers in the area of fiber-optic communications and holds 13 patents. Dr. Hui currently serves as an Associate Editor of IEEE Transactions on Communications. Maurice O'Sullivan has worked for Nortel for a score of years, at first in the optical cable business, developing factory-tailored metrology for optical fiber, but, in the main, in the optical transmission business developing, modeling and verifying physical layer designs & performance of Nortel's line and highest rate transmission product including OC-192, MOR, MOR+, LH1600G, eDCO and eDC40G. He holds a Ph.D. in physics (high resolution spectroscopy) from the University of Toronto, is a Nortel Fellow and has been granted more than 30 patents. * The only book to combine explanations of the basic principles with latest techniques to enable the engineer to develop photonic systems of the future * Careful and systematic presentation of measurement methods to help engineers to choose the most appropriate for their application * The latest methods covered, such as real-time optical monitoring and phase coded systems and subsystems, making this the most up-to-date guide to fiber optic measurement on the market "Fiber Optic Measurement Techniques is a collection of key optical measurement techniques essential for developing and characterizing today's photonic devices and fiber optic systems. The book gives comprehensive and systematic descriptions of various fiber optic measurement methods with the emphasis on the understanding of optoelectronic signal processing methodologies, helping the reader to weigh the pros and cons of each technique and establish its suitability for the task at hand." "This book brings together in one volume the fundamental principles and the latest techniques, making it a complete resource for the optical and communications engineer developing future optical devices and fiber optic system."--BOOK JACKET This book is an excellent reference in optical measurement. Actually there are not so many books combining theory and practical needs in the filed. The first one of such a book was Fiber Optic test and Measurement written by Derickson but updated. It is intended to be used by a practising engineer or scientist. Theoratical details are given only as much as necessary.