Introduction -- Propagation Effects in Optical and Wireless Communications Channels, Noise Sources, and Channel Impairments -- Components, Modules, and Subsystems -- Wireless and Optical Channels Capacities -- Advanced Modulation and Multiplexing Techniques -- Advanced Detection Techniques and Compensation of Channel Impairments -- OFDM for Wireless and Optical Communications -- Diversity and MIMO Techniques -- Advanced Coding and Coded Modulation Techniques -- Spread Spectrum, CDMA, and Ultra-Wideband Communications -- 5G/6G Technologies -- Physical-layer Security -- Conclusion.

The new edition of this popular textbook keeps its structure, introducing the advanced topics of: (i) wireless communications, (ii) free-space optical (FSO) communications, (iii) indoor optical wireless (IR) communications, and (iv) fiber-optics communications, but thoroughly updates the content for new technologies and practical applications. The author presents fundamental concepts, such as propagation principles, modulation formats, channel coding, diversity principles, MIMO signal processing, multicarrier modulation, equalization, adaptive modulation and coding, detection principles, and software defined transmission, first describing them and then following up with a detailed look at each particular system. The book is self-contained and structured to provide straightforward guidance to readers looking to capture fundamentals and gain theoretical and practical knowledge about wireless communications, free-space optical communications, and fiber-optics communications, all which can be readily applied in studies, research, and practical applications. The textbook is intended for upper undergraduate or graduate level courses in fiber-optics communication, wireless communication, and free-space optical communication.The book features exercises, an appendix with all background material needed, and homework problems. In the second edition, in addition to the existing chapters being updated and problems being inserted, one new chapter has been added, related to the physical-layer security thus covering both security and reliability issues. New material on 5G and 6G technologies has been added in corresponding chapters. Presents new and updated information on advanced optical and wireless communications systems; Includes new material on 5G/6G technologies, Includes a new chapter on physical-layer security issues; Features a full suite of classroom materials including exercises, Q&A, and examples.