Advanced Free Space Optics (FSO): A Systems Approach (Springer Series in Optical Sciences Book 186)

This title provides a comprehensive, unified tutorial covering the most recent advances in the emerging technology of free-space optics (FSO), a field in which interest and attention continue to grow along with the number of new challenges. This book is intended as an all-inclusive source to serve the needs of those who require information about the fundamentals of FSO, as well as up-to-date advanced knowledge of the state-of-the-art in the technologies available today. This text is intended for graduate students, and will also be useful for research scientists and engineers with an interest in the field. FSO communication is a practical solution for creating a three dimensional global broadband communications grid, offering bandwidths far beyond what is possible in the Radio Frequency (RF) range. However, the attributes of atmospheric turbulence and scattering impose perennial limitations on availability and reliability of FSO links. From a systems point-of-view, this groundbreaking book provides a thorough understanding of channel behavior, which can be used to design and evaluate optimum transmission techniques that operate under realistic atmospheric conditions. Topics addressed include: • FSO Physical and Statistical Models: Single/Multiple Inputs/Outputs • Understanding FSO: Theory and Systems Analysis • Modulation and Coding for Free-Space Optical Channels • Atmospheric Mitigation and Compensation for FSO Links • Non-line-of-sight (NLOS) Ultraviolet and Indoor FSO Communications • FSO Platforms: UAV and Mobile • Retromodulators for Free Space Data links • Hybrid Optical RF Communications • Free-space and Atmospheric Quantum Communications • Other related topics: Chaos-based and Terahertz (THz) FSO Communications Preface 6 Contents 12 Chapter-1 17 Fundamentals of Free-Space Optical (FSO) Communication System 17 1.1 Introduction 17 1.2 What is Information and how do we Measure it? 19 1.3 Bandwidth: Know the Data Transmission Rates and what you Need! 21 1.4 How the Data Transmission Rates are Provided in Today’s Networks 22 1.5 Basics of Optical Networks Relevant to FSO Communications 24 1.6 FSO Connectivity in Today’s Networks 25 1.7 Optical Networks: Integration of FSO 26 1.7.1 FSO Basic Architectures/Topologies 26 1.7.2 FSO Network: How to Implement? 27 1.7.3 Integrated FSO for Satellite, Terrestrial, and Home Networks. 28 1.8 FSO Mobile Ad-Hoc Networks (MANET) 31 1.9 Underwater FSO Communications Network 33 1.10 Indoor FSO Communications 35 References 36 Chapter-2 37 Theory of Free-Space Optical (FSO) Communication Signal Propagation Through Atmospheric Channel 37 2.1 Introduction 37 2.2 Statistical Description of Random Processes and Random Fields 38 2.2.1 Random Variables and Random Process 38 2.2.2 Characterizations of a Random Process 38 2.2.3 Power Spectral Density of Random Process 43 2.2.4 Concepts of Random Process for the Treatment of Random Fields 44 2.3 FSO Communications in Presence of Atmosphere 48 2.3.1 FSO Communication Scenarios 48 2.3.2 Flowchart for FSO Communication System Performance Evaluation 50 2.3.3 FSO Transmitting Beam Types 52 2.3.4 Random Nature of Atmospheric Turbulence 57 2.4 Theory of Optical Propagation Through Atmospheric Turbulence Relevant to FSO Communications: 61 2.5 FSO Communication Signal Temporal Frequency Spectrum 68 2.6 PDF Models for Intensity Fluctuations Relevant to FSO Communication Systems 69 2.7 Reconstruction of PDF of Intensity Fluctuations Relevant FSO Communications Through Atmospheric Turbulence 72 References 81 Chapter-3 84 Modulation, Detection, and Coding for Free-space Optical (FSO) Communications 84 3.1 Introduction 84 3.2 Digital Communications System: Modulation and Demodulation 85 3.3 FSO Communication Channel Models 86 3.3.1 Additive White Gaussian Noise (AWGN) Channel 86 3.3.2 Band-limited Channel 88 3.3.3 Fading and Randomly Varying Optical Channel 88 3.4 Modulation Schemes in FSO Communications 89 3.4.1 On-Off Keying (OOK) 90 3.4.2 Pulse position Modulation (PPM) 97 3.4.3 Binary Phase-Shift Keying (BPSK) Modulation 102 3.5 Channel Capacity and Coding for FSO Communications 111 3.5.1 Channel Capacity and Spectral Efficiency of FSO Channel 111 3.5.2 Coding Techniques as a FSO Link Aid 113 References 117 Chapter-4 119 Mitigation Techniques for Improved Free-space Optical (FSO) Communications 119 4.1 Introduction 119 4.2 Aperture Averaging 120 4.2.1 Aperture Averaging Technique 120 4.3 Diversity Technique 128 4.3.1 Spatial Diversity 129 4.3.2 Time diversity 142 4.3.3 Temporal-Domain Detection Techniques 147 4.3.4 Coding Techniques 154 4.3.5 Adaptive Optics (AO) Techniques 174 4.3.6 Other Techniques 182 References 187 Chapter-5 191 Non-Line-Of-Sight (NLOS) Ultraviolet And Indoor Free-Space Optical (FSO) Communications 191 5.1 Introduction 191 5.2 Ultraviolet Communications 192 5.3 NLOS FSO Communications Configurations and UV Source and Detector Technologies 193 5.3.1 NLOS UV Scattering Channel Model 194 5.3.2 Scattering-based NLOS Communication Performance Analysis 198 5.4 Indoor FSO Communications 204 5.4.1 Short Distance Systems 204 5.4.2 Indoor Link Configurations 205 5.4.3 Indoor Optical Wireless System 207 5.4.4 Propagation Modeling for Indoor Optical Wireless Communications 210 5.4.5 Recent Research in Indoor Optical Wireless Communications 214 Reference 215 Chapter-6 217 Free-space Optical (FSO) Platforms: Unmanned Aerial Vehicle (UAV) and MobileArun K. Majumdar 217 6.1 Introduction 217 6.2 UAV FSO Communications 218 6.2.1 UAV Scenarios for FSO Communications Link 218 6.2.2 Alignment and Tracking of a FSO Communications Link to a UAV 223 6.2.3 FSO Communication Links Using UAV(s): Practical Issues and Recent Development 225 6.3 Mobile FSO Communications 229 6.3.1 Beam Divergence and Power Levels Variations in Mobile FSO Communications 230 6.3.2 MANET FSO Communication Links 233 References 238 Chapter-7 240 Other Related Topics: Chaos-based and Terahertz (THz) FSO Communications 240 7.1 Introduction 240 7.2 Chaos-based FSO Communications 241 7.2.1 Basics of Chaotic Optical Communications 241 7.2.2 Chaotic FSO Communication over Atmospheric Turbulent Channel 242 7.2.3 Acousto-optic (AO) Chaos-based Secure FSO Communication Links 246 7.3 THz FSO Communications 247 7.3.1 Atmospheric Effects Relevant to thz FSO Communication Links 248 7.3.2 Indoor thz Communication 250 7.3.3 THz Wireless Communications Concepts and Hardware Development 251 References 254 Chapter-8 256 Modulating Retroreflector-based Free-space Optical (FSO) Communications 256 8.1 Introduction 256 8.2 Introduction and Background 256 8.3 Description of MRR FSO Communications System 258 8.4 MRR Technologies 258 8.4.1 EOMs 260 8.4.2 AOModulation 265 8.4.3 Liquid Crystal (LC)/Ferroelectric Liquid Crystal (FLC)-based Modulators FLC Modulators 267 8.4.4 MQW Technology for Modulation MQW Modulators 270 8.4.5 MEMS Deformable Mirror Retroreflector Modulators 273 8.4.6 Fiber-based Amplified-Retro-Modulator (ARM): A New Concept in MRR Technology Amplified Retro-Modulator (ARM) based on single-mode optical fiber (SMF) 279 8.5 MRR-based FSO Communications Systems Performance Analysis 284 8.5.1 Link Budget Analysis 285 8.5.2 Quantifying the Link Budget 286 8.5.3 BER Calculation for MRR System in Presence Atmospheric Turbulence 288 8.5.4 Atmospheric Scattering Effects on MRR-FSO Communications System 295 8.6 Applications 298 References 304 Chapter-9 307 Hybrid Optical/Radio Frequency (RF) Communications 307 9.1 Introduction 307 9.2 Hybrid Optical/RF Communications 308 9.2.1 ORCA Program and Objective Hybrid System Description 310 9.2.2 FSOC System Overview 311 9.2.3 RF Subsystem Overview 313 9.2.4 Network Subsystem Overview 313 9.3 FSOC Systems 315 9.3.1 Background 315 9.3.2 FSOC System Performance Modeling 316 9.3.3 Scintillation Mitigation Techniques 322 9.3.4 FSOC Experimental Results 328 9.4 RF Communications System 336 9.4.1 RF Subsystems 336 9.4.2 RF Channel Model 337 9.4.3 DFE Performance Model 338 9.4.4 RFC SNR 344 9.4.5 Equalizer Performance Validation 344 9.5 Network System 347 9.5.1 Network Architecture 347 9.5.2 Network Analysis 348 9.5.3 Packet Loss Mitigation Techniques and Effects on Packet Latency 350 9.5.4 Improved Retransmission Performance 352 References 353 Chapter-10 355 Free-Space and Atmospheric Quantum Communications 355 10.1 Introduction to Free-Space and Atmospheric Quantum Communications 355 10.2 Fundamentals for Free-Space Quantum Communications 356 10.2.1 Introduction 356 10.2.2 Fundamentals 357 10.2.3 The Concepts of Information Content and Quantum Information 362 10.2.4 Quantum Optics 362 10.2.5 Quantum Sources 363 10.2.6 Quantum Measurement Processes 363 10.2.7 Quantum Squeezing 365 10.2.8 Measurement Bases Used in Quantum Protocols 365 10.2.9 Spontaneous Parametric Downconversion (SPDC) and Upconversion 368 10.2.10 Random Number Generation By Quantum Physics Versus the Pseudo-Random Number Generation of Classical Encryption 369 10.2.11 No-Cloning Theorem 369 10.2.12 Weak Coherence 370 10.2.13 Entangled Photon Quantum Communications 371 10.2.14 Quantum Cryptography and Quantum Key Distribution 372 10.3 Free-Space and Atmospheric Quantum Communications Experiments 380 10.3.1 Introduction 380 10.3.2 Ground-to-ground, Ground-to-aircraft and Ground-to-satellite Experiments 381 10.3.2.1 Representative Quantum Communications Experiments (QKD and Polarization Entanglement) in the Laboratory 387 10.3.3 Summary 388 10.3.4 Exercises 391 References 391 Index 400 This Book Provides A Comprehensive, Unified Tutorial Covering The Most Recent Advances In The Technology Of Free-space Optics (fso). It Is An All-inclusive Source Of Information On The Fundamentals Of Fso As Well As Up-to-date Information On The State-of-the-art In Technologies Available Today. This Text Is Intended For Graduate Students, And Will Also Be Useful For Research Scientists And Engineers With An Interest In The Field. Fso Communication Is A Practical Solution For Creating A Three Dimensional Global Broadband Communications Grid, Offering Bandwidths Far Beyond What Is Possible In The Radio Frequency (rf) Range. however, The Attributes Of Atmospheric Turbulence And Scattering Impose Perennial Limitations On Availability And Reliability Of Fso Links. from A Systems Point-of-view, This Groundbreaking Book Provides A Thorough Understanding Of Channel Behavior, Which Can Be Used To Design And Evaluate Optimum Transmission Techniques That Operate Under Realistic Atmospheric Conditions. Topics Addressed Include: • Fso Physical And Statistical Models: Single/multiple Inputs/outputs • Understanding Fso: Theory And Systems Analysis • Modulation And Coding For Free-space Optical Channels • Atmospheric Mitigation And Compensation For Fso Links • Non-line-of-sight (nlos) Ultraviolet And Indoor Fso Communications • Fso Platforms: Uav And Mobile • Retromodulators For Free Space Data Links • Hybrid Optical Rf Communications • Free-space And Atmospheric Quantum Communications • Other Related Topics: Chaos-based And Terahertz (thz) Fso Communications Chapter 1 Fundamentals Of Fso Communication System -- 1.1 Introduction -- 1.2 What Is Information And How Do We Measure It? -- 1.3 Bandwidth: Know The Data Transmission Rates And What You Need! -- 1.4 How The Data Transmission Rates Are Provided In Today’s Networks -- 1.5 Basics Of Optical Networks Relevant To Fso Communications -- 1.6 Free-space Optical Connectivity In Today’s Networks -- 1.7 Optical Networks: Integration Of Fso -- 1.8 Free-space-optical (fso) Mobile Ad-hoc Networks (manet) -- 1.9 Underwater Free-space-optical ( Fso) Communications Network -- 1.10 Indoor Fso Communications -- Chapter 2 Theory Of Fso Communication Signal Propagation Through Atmospheric Channel -- 2.1 Statistical Description Of Random Processes And Random Fields -- 2.2 Fso Communications In Presence Of Atmosphere -- 2.3 Theory Of Optical Propagation Through Atmospheric Turbulence Relevant To Fso Optical Communications -- 2.4 Fso Communication Signal Temporal Frequency Spectrum --^ 2.5 Probability Density Function (pdf) Models For Intensity Fluctuations Relevant To Fso Communication Systems -- 2.6 Reconstruction Of Probability Density Function Of Intensity Fluctuations Relevant Fso Communications Through Atmospheric Turbulence -- Chapter 3 Modulation, Detection And Coding For Fso Communications -- 3.1 Digital Communications System: Modulation And Demodulation -- 3.2 Fso Communication Channel Models -- 3.3 Modulation Schemes In Fso Communications -- 3.4 Channel Capacity And Coding For Fso Communications -- Chapter 4 Mitigation Techniques For Improved Fso Communications -- 4.1 Aperture Averaging -- 4.2 Diversity Technique -- Chapter 5. Non-line-of-sight (nlos) Ultraviolet And Indoor Fso Communications -- 5.1 Ultraviolet Communications -- 5.2 Nlos Fso Communications Configurations And Uv Source And Detector Technologies -- 5.3 Indoor Fso Communications -- Chapter 6 Fso Platforms: Uav And Mobile --^ 6.1 Unmanned Aerial Vehicle (uav) Free Space Optical Communications -- 6.2 Mobile Free Space Optical Communications -- 7. Other Related Topics: Chaos-based And Terahertz (thz) Fso Communications -- 7.1 Chaos-based Fso Communications -- 7.2 Terahertz (thz) Fso Communications -- Chapter 8 Modulating Retro-reflector-based Fso Communications -- 8.1. Introduction And Background -- 8.2. Description Of Modulating Retro-reflector Free-space Optical Communications System -- 8.3. Modulating Retro-reflector Technologies -- 8.4. Mrr-based Fso Communications Systems Performance Analysis -- 8.5. Applications -- Chapter 9 Hybrid Optical/rf Communications -- 9.1 Introduction -- 9.2 Hybrid Optical/rf Communications -- 9.3 Free Space Optical Communication Systems -- 9.4 Rf Communications System -- 9.5 Network System -- Chapter 10. Free-space And Atmospheric Quantum Communications -- 10.1 Introduction To Free-space And Atmospheric Quantum Communications --^ 10.2 Fundamentals For Free-space Quantum Communications -- 10.3 Free-space And Atmospheric Quantum Communications Experiments. By Arun K. Majumdar. Front Matter....Pages i-xv Fundamentals of Free-Space Optical (FSO) Communication System....Pages 1-20 Theory of Free-Space Optical (FSO) Communication Signal Propagation Through Atmospheric Channel....Pages 21-67 Modulation, Detection, and Coding for Free-space Optical (FSO) Communications....Pages 69-103 Mitigation Techniques for Improved Free-space Optical (FSO) Communications....Pages 105-176 Non-Line-Of-Sight (NLOS) Ultraviolet And Indoor Free-Space Optical (FSO) Communications....Pages 177-202 Free-space Optical (FSO) Platforms: Unmanned Aerial Vehicle (UAV) and Mobile....Pages 203-225 Other Related Topics: Chaos-based and Terahertz (THz) FSO Communications....Pages 227-242 Modulating Retroreflector-based Free-space Optical (FSO) Communications....Pages 243-293 Hybrid Optical/Radio Frequency (RF) Communications....Pages 295-342 Free-Space and Atmospheric Quantum Communications....Pages 343-387 Back Matter....Pages 389-397