This book provides an in-depth understanding of free space optical (FSO) communication with a particular emphasis on optical beam propagation through atmospheric turbulence. The book is structured in such a way that it provides a basic framework for the beginners and also gives a concise description from a designer's perspective. The book provides an exposure to FSO technology, fundamental limitations, design methodologies, system trade-offs, acquisition, tracking and pointing (ATP) techniques and link-feasibility analysis. The contents of this book will be of interest to professionals and researchers alike. The book may also be used as a textbook for engineering coursework and professional training.

Hemani Kaushal is currently working as Associate Professor at The NorthCap University (former name ITM University), Gurgaon, India. Dr. Kaushal received her Ph. D degree from the Electrical Engineering Department, Indian Institute of Technology Delhi (IITD), New Delhi, India. She completed her Master of Engineering in Electronics Product Design and Technology from the Punjab Engineering College University of Technology (PECUT), Chandigarh and Bachelor's degree in Electronics and Communication Engineering from Punjab Technical University (PTU), Punjab, India. She has worked on various industry sponsored projects related to free space optical communication for Indian Space Research Organization (ISRO) and Aeronautical Development Agency (ADA), India. Her areas of research include wireless communication systems specifically in free-space, underwater, and indoor visible-light optical communications. She has over 30+ publications in international journals and conferences. She has received best presentation award in International Conference on Light: OPTICS'11 held at National Institute of Technology (NIT), Calicut, Kerala, India in May 2011. She also received second best award on National Science Day held at IIT Delhi in Feb 2011. She is a life member of Indian Society of Technical Education (ISTE) and member of Institute of Electrical and Electronics Engineers (IEEE), USA.

Virander Kumar Jain is working as Professor of Electrical Engineering at IIT Delhi. He obtained his Master of Science (Electronics) degree in 1973 from the Meerut University, India. He did M.Sc. (Tech.) in Electronics from the Birla Institute of Technology and Science (BITS) Pilani in 1975. He completed his Ph. D in Communication Engineering from IIT Delhi. His research areas are photonics switching and networking, optical fiber and optical space communications, optoelectronic instrumentation, wireless communications, digital communications, noise study and modeling. He has published over 160 papers in various International and National journals and conferences. He has also co-authored 2 books entitled "Optical Communication Systems" and "Optical Communications: Components and Systems". He is a life member of ISTE, Senior Member, IEEE and Fellow, Institution of Electronics and Telecommunication Engineers (IETE), India.

Subrat Kar is a Professor of Electrical Engineering at IIT Delhi. His research interests are optics, embedded telecom systems, telecom transmission and switching, automotive networks, deep space communications and bio-medical instrumentation. Dr. Kar has over 80 journal publications to his credit. He has also co-authored a book titled "Optical Fiber Communication: Principles and Systems".