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Quantum communication theory is receiving much attention as the basis for practical optical communications and quantum measurements. This book is a unique survey of the activities of the leading research groups from mathematical physics, information theory, and various areas in quantum optics. The contributions deal with both theory and foundations of quantum physics together with technical applications.

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Quantum limits of measurements and uncertainty principle.- A quantum experiment uncertainty principle: A general 2nd moment uncertainty relation.- Quantum mechanical description of light propagation.- Quantum propagation in optical fibres.- The uncertainty principle in a QND measurement of photon number.- Some remarks on the phase operator in quantum optics.- Quantum state control and nonlinear schr?dinger equation.- Quantum entropy and quantum measurements.- Information dynamics and its applications to optical communication processes.- Information theory and quantum correlations.- Physical information theory for 30 years: Basic concepts and results.- Quantum nondemolition measurement in optical communication theory.- Information in quantum optical communications.- Statistical inference for quantum processes.- A new class of quantum states: Examples and applications.- Continuous non-demolition observation quantum filtering and optimal estimation.- Entropy production and nonequilibrium stationarity in quantum dynamical systems.- Detection theory in quantum optics and quantum stochastic calculus.- Calculating photocount distributions by saddlepoint methods.- Rigorous derivation of error probability in coherent optical communication.- Comparison of ppam and ppm formats in photon counting channels.- Optical communication with coherent squeezed state. Realization of received quantum state control.- A new method for improving the bandwidth utilization efficiency in optical PPM.- Properties of system using spatial multi-mode squeezer.- Achievement of new quantum limit by switching of pump frequency of squeezer.- Information transmission with squeezed light.- Twin photons and squeezed light.- A new definition and generalization of squeezed states.- Squeezing of a filtered thermal field in a degenerated parametric optical amplifier.- Displaced number states.- Generalized quadratic generator of squeezed states.- Thermal states with variances smaller than vacuum variances.- Squeezing-symmetry of the balanced homodyne detector.- Optical communication with novel quantum devices.- Construction of modulator for quantum orthogonal signal by Bright Squeezer.- Efficiency of optical modulations with coherent state.- An optical system at the quantum limit of coherent detection: The wind lidar.- Simulation of optimum quantum receiver.- Gain, saturation and noise figure of a travelling wave semiconductor optical amplifier.- Oral presentation.

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Leading theoretical and applied groups give here a unique survey of quantum-optical communication and quantum measurements. In this important field of practically oriented research there is a close relation between foundations and their applications in technology.

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