The original edition dates back to the late 1980s / early 1990s, so it lacks coverage of modern advances: DWDM, coherent detection, digital signal processing, advanced modulation formats, and modern optical amplifiers (beyond basic EDFA introduction). Some component technologies (lasers, detectors) are dated. Figures and notation may feel old-fashioned.
"Optical Communication Systems" by John Gowar is a detailed textbook that covers the fundamental principles of optical communication systems. The book provides a thorough analysis of the subject, starting from the basics of optical communication systems to advanced topics such as wavelength division multiplexing (WDM) and optical networks. optical communication system by john gowar pdf
The Light Between Cities
Published in 1984 (and reprinted with corrections in the 1990s), John Gowar’s Optical Communication Systems remains a classic textbook in the field of fiber-optic communications. Unlike many modern texts that focus heavily on recent advances (e.g., coherent detection, digital signal processing, or space-division multiplexing), Gowar’s work is prized for its treatment of fundamental principles. It bridges the gap between pure physics (semiconductor lasers, photodetectors) and system engineering (power budgets, rise-time budgets, noise analysis). For students, researchers, and practicing engineers, the book offers a timeless foundation. The original edition dates back to the late