6 Result(s)
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Tsuyoshi Sasaki Usuda
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Article
Open AccessSecurity enhancement of amplitude-shift keying-type asymmetric quantum communication systems
Recently, we proposed an amplitude-shift keying asymmetric quantum communication system and evaluated its reliability when using the quasi-Bell state and two-mode squeezed vacuum state (TSVS) as an entangled l...
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Chapter
Superadditivity in Capacity of Quantum Channel by Classical Pseudo-Cyclic Codes
Analytical solution of mutual information by square-root measurement for binary linear code is given. Applying the solution, we show properties of superadditivity in capacity by BCH codes with codeword length ...
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Chapter
Group Covariant Signals in Quantum Information Theory
Necessary and sufficient condition for group covariant signals is given. This condition shows what kind of signals correspond to “group covariant signals.” We show by applying this condition that many signals,...
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Chapter
Property of Mutual Information for M-ary Quantum-State Signals
Numerical solutions of maximum mutual information for 3-ary phase-shift keyed coherent-state signals and 3-ary real-symmetric (lifted trine) signals, which are linearly independent signals, are shown. A condit...
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Chapter
On the Realization of Received Quantum State Control by Unitary Transformation
Necessary and sufficient conditions of an optimum pair of signals for given decision operators are given. These conditions show what kind of signals are desired for the output of the unitary transformation in ...
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Chapter
An Example of a Received Quantum State Controller by Optical Kerr Effect
According to recent development of optical technology, performance of optical communication system almost achieves the theoretical limitation predicted by classical communication theory, which is so called sta...
