Salient Features Extensive coverage of topics related to optical fiber communications. Useful for GATE, NET/SLET, UGC–CSIR and other entrance and competitive examinations. Appendices with the list of abbreviations, physical constants, standard international units, Bessel's functions, and some useful mathematical relations, etc. are given for quick reference. Special emphasis on optical sources-LASER and LED. Simple language and lucid style of presentation. Supplemented with elaborate illustrations, worked out problems, summary, review questions for self-evaluation, short-answer questions and multiple choice questions with answers