Optical Wireless Communications

Professor Zabih Ghassemlooy (CEng, Fellow of IET, senior member of IEEE) received his BSc (Hons.) in electrical and electronics engineering from the Manchester Metropolitan University in 1981, and his MSc and Ph.D in optical communications from the University of Manchester Institute of Science and Technology thereafter in 1984 and 1987, respectively. Currently he is an associate dean for research in the School of Computing, Engineering and Information Sciences, University of Northumbria at Newcastle upon Tyne, UK. He also heads the Northumbria Communications Research Laboratories within the school. His research interests are mainly in the area of optical communications, and published over 415 papers. He is the founder and the chairman of the IEEE, IET International Symposium on Communication Systems, Network and Digital Signal Processing. Dr. W. Popoola had his national diploma in electrical engineering from The Federal Polytechnic, Ilaro, Nigeria and later graduated with first class honours degree in electronic and electrical engineering from Obafemi Awolowo University, Nigeria. He later proceeded to Northumbria University at Newcastle upon Tyne, England, UK, for his MSc in optoelectronic and communication systems where he graduated with distinction in 2006. He was awarded his Ph.D. in 2009 at the Northumbria University for his research work in free-space optical communications. He is currently a researcher with the Institute for Digital Communications, University of Edinburgh, UK working on visible light communications. Dr. S. Rajbhandari obtained his bachelor degree in electronics and communication engineering from the Institute of Engineering, Pulchowk Campus (Tribhuvan University), Nepal in 2004. In 2006, he received an MSc in optoelectronic and communication systems with distinction and was awarded the P. O. Byrne prize for most innovative project. He then joined the Optical Communications Research Lab (OCRG) at Northumbria University and was awarded a Ph.D degree in 2010. Since 2009, he has been with the OCRG at Northumbria University working as a postdoctoral researcher. He has published more than 70 scholarly articles in the area of optical wireless communications.

Introduction: Optical Wireless Communication Systems


Wireless Access Schemes


A Brief History of OWC


OWC/Radio Comparison


Link Configuration


OWC Application Areas


Safety and Regulations


OWC Challenges






Optical Sources and Detectors


Light Sources


Light-Emitting Diode


The Laser


Photodetectors


Photodetection Techniques


Photodetection Noise


Optical Detection Statistics






Channel Modelling


Indoor Optical Wireless Communication Channel


Artificial Light Interference


Outdoor Channel






Modulation Techniques


Introduction


Analogue Intensity Modulation


Digital Baseband Modulation Techniques


Pulse Position Modulation


Pulse Interval Modulation


Dual-Header PIM


Multi-Level DPIM


Comparisons of Baseband Modulation Schemes


Subcarrier Intensity Modulation


Orthogonal Frequency Division Multiplexing


Optical Polarization Shift Keying


Appendices






System Performance Analysis: Indoor


Effect of Ambient Light Sources on Indoor OWC Link Performance


Effect of FLI without Electrical High-Pass Filtering


Effect of Baseline Wander without FLI


Effect of FLI with Electrical High-Pass Filtering


Wavelet Analysis


Link Performance for Multi-path Propagation


Mitigation Techniques


Equalization as a Classification Problem


Introduction to Artificial Neural Network


Training Network


The ANN-Based Adaptive Equalizer






FSO Link Performance under the Effect of Atmospheric Turbulence


On–Off Keying


Pulse Position Modulation


Subcarrier Intensity Modulation


Atmospheric Turbulence-Induced Penalty


Appendices






Outdoor OWC Links with Diversity Techniques


Atmospheric Turbulence Mitigation Techniques


Receiver Diversity in Log-Normal Atmospheric Channels


Transmitter Diversity in a Log-Normal Atmospheric Channel


Transmitter–Receiver Diversity in a Log-Normal Atmospheric Channel


Results and Discussions of SIM-FSO with Spatial Diversity in a Log-Normal Atmospheric Channel


SIM-FSO with Receiver Diversity in Gamma–Gamma and Negative Exponential Atmospheric Channels


Terrestrial Free Space Optical Links with Subcarrier Time Diversity


Aperture Averaging


Appendices






Visible Light Communications


Introduction


System Description


System Implementations


Multiple-Input-Multiple-Output VLC


Home Access Network


References