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arXiv · 1308.2036

Performance gain of displacement receiver with optimized prior probability

M. Fujiwara·S. Izumi·M. Takeoka·M. Sasaki
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Abstract

We numerically study the performance of the displacement based quantum receiver for the discrimination of weak 3- and 4-phase-shift keyed (PSK) coherent state signals. We show that due to the nontrivial asymmetry of the receiver structure, optimization of the prior probability increases the mutual information and achieves sub-shot-noise limit discrimination. Moreover, we estimate the cutoff rate for a 4-PSK signal and confirm that the prior probability optimization shortens the code length for a given decoding error criterion. Such consideration for the asymmetric channel matrix is essential in a study of the compassable quantum receiver.

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M. Fujiwara, S. Izumi, M. Takeoka, M. Sasaki. 2013-08-09. Performance gain of displacement receiver with optimized prior probability. https://doi.org/10.1016/j.physleta.2013.08.018

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