Quantum Communications

Quantum Communications demonstrates that a quantum communication system using the coherent light of a laser can achieve performance orders of magnitude superior to classical optical communications.§The text provides the Masters and PhD signals or communications student with a complete basics-to-applications course in using the principles of quantum mechanics to provide cutting-edge telecommunications. Assuming only knowledge of elementary probability, complex analysis and optics, the book guides its reader through the fundamentals of vector and Hilbert spaces and the necessary quantum-mechanical ideas, simply formulated in four postulates. A turn to practical matters begins with and is then developed by:§§development of the concept of quantum decision, emphasizing the optimization of measurements to extract useful information from a quantum system;§general formulation of a transmitter receiver system;§particular treatment of the most popular quantum communications systems OOK, PPM, PSK and QAM;§more realistic performance evaluation introducing thermal noise and system description with density operators;§consideration of scarce existing implementations of quantum communications systems and their difficulties with suggestions for future improvement; and§separate treatment of quantum information with discrete and continuous states. Quantum Communications develops the engineering student s exposure to quantum mechanics and shows physics students that its theories can have practically beneficial application in communications systems. The use of example and exercise questions (together with a downloadable solutions manual for instructors) will help to make the material presented really sink in for students and invigorate subsequent research.