Optical Wireless Communications

Book description

Detailing a systems approach, Optical Wireless Communications: System and Channel Modelling with MATLAB®, is a self-contained volume that concisely and comprehensively covers the theory and technology of optical wireless communications systems (OWC) in a way that is suitable for undergraduate and graduate-level students, as well as researchers and professional engineers.

Incorporating MATLAB® throughout, the authors highlight past and current research activities to illustrate optical sources, transmitters, detectors, receivers, and other devices used in optical wireless communications. They also discuss both indoor and outdoor environments, discussing how different factors—including various channel models—affect system performance and mitigation techniques.

In addition, this book broadly covers crucial aspects of OWC systems:

  • Fundamental principles of OWC
  • Devices and systems
  • Modulation techniques and schemes (including polarization shift keying)
  • Channel models and system performance analysis
  • Emerging visible light communications
  • Terrestrial free space optics communication
  • Use of infrared in indoor OWC

One entire chapter explores the emerging field of visible light communications, and others describe techniques for using theoretical analysis and simulation to mitigate channel impact on system performance. Additional topics include wavelet denoising, artificial neural networks, and spatial diversity. Content also covers different challenges encountered in OWC, as well as outlining possible solutions and current research trends. A major attraction of the book is the presentation of MATLAB simulations and codes, which enable readers to execute extensive simulations and better understand OWC in general.

Table of contents

  1. Cover Page
  2. Title Page
  3. Copy Page
  4. Dedication
  5. Preface
  6. Preface
  7. Authors
  8. List of Figures
  9. List of Tables
  10. Abbreviations
  11. Chapter 1 Introduction Optical Wireless Communication Systems
    1. 1.1 Wireless Access Schemes
    2. 1.2 A Brief History of OWC
    3. 1.3 OWC/Radio Comparison
    4. 1.4 Link Configuration
    5. 1.5 OWC Application Areas
    6. 1.6 Safety and Regulations
      1. 1.6.1 Maximum Permissible Exposures
    7. 1.7 OWC Challenges
    8. 1.8 References
  12. Chapter 2 Optical Sources and Detectors
    1. 2.1 Light Sources
    2. 2.2 Light-Emitting Diode
      1. 2.2.1 LED Structure
      2. 2.2.2 Planar and Dome LED
      3. 2.2.3 Edge-Emitting LED
      4. 2.2.4 LED Efficiencies
        1. 2.2.4.1 Internal Quantum Efficiency
        2. 2.2.4.2 External Quantum Efficiency
        3. 2.2.4.3 Power Efficiency
        4. 2.2.4.4 Luminous Efficiency
        5. 2.2.4.5 LED Modulation Bandwidth
    3. 2.3 The Laser
      1. 2.3.1 Operating Principle of a Laser
      2. 2.3.2 Stimulated Emission
        1. 2.3.2.1 Population Inversion
      3. 2.3.3 Optical Feedback and Laser Oscillation
      4. 2.3.4 Basic Semiconductor Laser Structure
      5. 2.3.5 The Structure of Common Laser Types
        1. 2.3.5.1 Fabry–Perot Laser
        2. 2.3.5.2 Distributed Feedback Laser
        3. 2.3.5.3 Vertical-Cavity Surface-Emitting Laser
        4. 2.3.5.4 Superluminescent Diodes
      6. 2.3.6 Comparison of LED and Laser Diodes
    4. 2.4 Photodetectors
      1. 2.4.1 Pin Photodetector
      2. 2.4.2 APD Photodetector
    5. 2.5 Photodetection Techniques
      1. 2.5.1 Direct Detection
      2. 2.5.2 Coherent Detection
        1. 2.5.2.1 Heterodyne Detection
        2. 2.5.2.2 Homodyne Detection
    6. 2.6 Photodetection Noise
      1. 2.6.1 Photon Fluctuation Noise
      2. 2.6.2 Dark Current and Excess Noise
      3. 2.6.3 Background Radiation
      4. 2.6.4 Thermal Noise
      5. 2.6.5 Intensity Noise
      6. 2.6.6 Signal-to-Noise Ratio
    7. 2.7 Optical Detection Statistics
    8. References
  13. Chapter 3 Channel Modelling
    1. 3.1 Indoor Optical Wireless Communication Channel
      1. 3.1.1 Los Propagation Model
      2. 3.1.2 Non-LOS Propagation Model
      3. 3.1.3 Ceiling Bounce Model
      4. 3.1.4 Hayasaka–Ito Model
      5. 3.1.5 Spherical Model
    2. 3.2 Artificial Light Interference
      1. 3.2.1 Incandescent Lamp
      2. 3.2.2 Fluorescent Lamp Driven by Conventional Ballast
      3. 3.2.3 Fluorescent Lamp Model
    3. 3.3 Outdoor Channel
      1. 3.3.1 Atmospheric Channel Loss
      2. 3.3.2 Fog and Visibility
      3. 3.3.3 Beam Divergence
      4. 3.3.4 Optical and Window Loss
      5. 3.3.5 Pointing Loss
      6. 3.3.6 The Atmospheric Turbulence Models
        1. 3.3.6.1 Log-Normal Turbulence Model
        2. 3.3.6.2 Spatial Coherence in Weak Turbulence
        3. 3.3.6.3 Limit of Log-Normal Turbulence Model
        4. 3.3.6.4 The Gamma–Gamma Turbulence Model
        5. 3.3.6.5 The Negative Exponential Turbulence Model
      7. 3.3.7 Atmospheric Effects On OWC Test Bed
        1. 3.3.7.1 Demonstration of Scintillation Effect on Data Carrying Optical Radiation
    4. References
  14. Chapter 4 Modulation Techniques
    1. 4.1 Introduction
    2. 4.2 Analogue Intensity Modulation
    3. 4.3 Digital Baseband Modulation Techniques
      1. 4.3.1 Baseband Modulations
      2. 4.3.2 On–Off Keying
      3. 4.3.3 Error Performance on Gaussian Channels
    4. 4.4 Pulse Position Modulation
      1. 4.4.1 Error Performance on Gaussian Channels
      2. 4.4.2 PPM Variants
        1. 4.4.2.1 Multilevel PPM
        2. 4.4.2.2 Differential PPM
        3. 4.4.2.3 Differential Amplitude Pulse Position Modulation
    5. 4.5 Pulse Interval Modulation
      1. 4.5.1 Error Performance on Gaussian Channels
        1. 4.5.1.1 DPIM with No Guard Band
        2. 4.5.1.2 DPIM with One Guard Slot
      2. 4.5.2 Optimum Threshold Level
    6. 4.6 Dual-Header PIM (DH-PIM)
      1. 4.6.1 Spectral Characteristics
      2. 4.6.2 Error Performance on Gaussian Channels
    7. 4.7 Multilevel DPIM
    8. 4.8 Comparisons of Baseband Modulation Schemes
      1. 4.8.1 Power Efficiency
      2. 4.8.2 Transmission Bandwidth Requirements
      3. 4.8.3 Transmission Capacity
      4. 4.8.4 Transmission Rate
      5. 4.8.5 Peak-to-Average Power Ratio
    9. 4.9 Subcarrier Intensity Modulation
    10. 4.10 Orthogonal Frequency Division Multiplexing
    11. 4.11 Optical Polarization Shift Keying
      1. 4.11.1 Binary Polsk
      2. 4.11.2 Bit Error Rate Analysis
      3. 4.11.3 MPolSK
      4. 4.11.4 Differential Circle Polarization Shift Keying
      5. 4.11.5 Error Probability Analysis
    12. References
  15. Chapter 5 System Performance Analysis Indoor
    1. 5.1 Effect of Ambient Light Sources on Indoor OWC Link Performance
    2. 5.2 Effect of FLI without Electrical High-Pass Filtering
      1. 5.2.1 Matched Filter Receiver
    3. 5.3 Effect of Baseline Wander Without FLI
    4. 5.4 Effect of FLI with Electrical High-Pass Filtering
    5. 5.5 Wavelet Analysis
      1. 5.5.1 The Continuous Wavelet Transform
      2. 5.5.2 The Discrete Wavelet Transform
      3. 5.5.3 DWT-Based Denoising
      4. 5.5.4 Comparative Study of DWT and HPF
      5. 5.5.5 Experimental Investigations
    6. 5.6 Link Performance for Multipath Propagation
      1. 5.6.1 OOK
      2. 5.6.2 PPM
      3. 5.6.3 DPIM
    7. 5.7 Mitigation Techniques
      1. 5.7.1 Filtering
      2. 5.7.2 Equalization
        1. 5.7.2.1 The Zero Forcing Equalizer
        2. 5.7.2.2 Minimum Mean Square Error Equalizer
        3. 5.7.2.3 Decision Feedback Equalizer
    8. 5.8 Equalization as a Classification Problem
    9. 5.9 Introduction to Artificial Neural Network
      1. 5.9.1 Neuron
      2. 5.9.2 ANN Architectures
    10. 5.10 Training Network
      1. 5.10.1 Backpropagation Learning
    11. 5.11 The ANN-Based Adaptive Equalizer
      1. 5.11.1 Comparative Study of the ANN- and FIR-Based Equalizers
      2. 5.11.2 Diversity Techniques
    12. References
  16. Chapter 6 FSO Link Performance under the Effect of Atmospheric Turbulence
    1. 6.1 ON–OFF Keying
      1. 6.1.1 OOK in a Poisson Atmospheric Optical Channel
      2. 6.1.2 OOK in a Gaussian Atmospheric Optical Channel
    2. 6.2 Pulse Position Modulation
    3. 6.3 Subcarrier Intensity Modulation
      1. 6.3.1 SIM Generation and Detection
      2. 6.3.2 SIM-FSO Performance in Log-Normal Atmospheric Channel
      3. 6.3.3 Bit Error Probability Analysis of SIM-FSO
        1. 6.3.3.1 BPSK-Modulated Subcarrier
        2. 6.3.3.2 M-Ary PSK-Modulated Subcarrier
        3. 6.3.3.3 DPSK-Modulated Subcarrier
        4. 6.3.3.4 Multiple SIM Performance Analysis
        5. 6.3.3.5 Outage Probability in Log-Normal Atmospheric Channels
      4. 6.3.4 SIM-FSO Performance in Gamma–Gamma and Negative Exponential Atmospheric Channels
      5. 6.3.5 Outage Probability in Negative Exponential Model Atmospheric Channels
    4. 6.4 Atmospheric Turbulence-Induced Penalty
    5. References
  17. Chapter 7 Outdoor OWC Links with Diversity Techniques
    1. 7.1 Atmospheric Turbulence Mitigation Techniques
    2. 7.2 Receiver Diversity in Log-Normal Atmospheric Channels
      1. 7.2.1 Maximum Ratio Combining
      2. 7.2.2 Equal Gain Combining
      3. 7.2.3 Selection Combining
      4. 7.2.4 Effect of Received Signal Correlation on Error Performance
      5. 7.2.5 Outage Probability with Receiver Diversity in a Log-Normal Atmospheric Channel
    3. 7.3 Transmitter Diversity in a Log-Normal Atmospheric Channel
    4. 7.4 Transmitter–Receiver Diversity in a Log-Normal Atmospheric Channel
    5. 7.5 Results and Discussions of SIM-FSO with Spatial Diversity in a Log-Normal Atmospheric Channel
    6. 7.6 SIM-FSO with Receiver Diversity in Gamma–Gamma and Negative Exponential Atmospheric Channels
      1. 7.6.1 BER and Outage Probability of BPSK-SIM with Spatial Diversity
      2. 7.6.2 BER and Outage Probability of DPSK-SIM in Negative Exponential Channels
    7. 7.7 Terrestrial Free Space Optical Links with Subcarrier Time Diversity
      1. 7.7.1 Error Performance with STDD
        1. 7.7.1.1 Error Performance of Short-Range Links
        2. 7.7.1.2 Error Performance of Long-Range Links
        3. 7.7.1.3 Results and Discussion for Short-Range Links
        4. 7.7.1.4 Results and Discussion for Long-Range Links
    8. 7.8 Aperture Averaging
      1. 7.8.1 Plane Wave
      2. 7.8.2 Spherical Wave
      3. 7.8.3 Gaussian Beam Wave
    9. References
  18. Chapter 8 Visible Light Communications
    1. 8.1 Introduction
    2. 8.2 System Description
      1. 8.2.1 VLC System Model
      2. 8.2.2 SNR Analysis
      3. 8.2.3 Channel Delay Spread
    3. 8.3 System Implementations
      1. 8.3.1 Bit Angle Modulation
      2. 8.3.2 Pulse Modulation Schemes
      3. 8.3.3 PWM with Discrete Multitone Modulation
      4. 8.3.4 Multilevel PWM-PPM
      5. 8.3.5 PWM with NRZ-OOK
    4. 8.4 Multiple-Input–Multiple-Output VLC
    5. 8.5 Home Access Network
    6. References
  19. Index

Product information

  • Title: Optical Wireless Communications
  • Author(s): Z. Ghassemlooy, W. Popoola, S. Rajbhandari
  • Release date: July 2017
  • Publisher(s): CRC Press
  • ISBN: 9781351833257