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arXiv · 2606.31541

Inverse-squeezing receivers for squeezed-state pulse-position modulation under ideal and phase-diffusion conditions

Enhao Bai·Fengkai Sun·Tianyi Wu·Huankai Zhang·Jian Peng·Chen Dong·Zhenrong Zhang
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Abstract

We introduce a squeezed-state pulse-position modulation (S-PPM) format, where the empty slots are squeezed vacuum states and the pulse slot is a displaced squeezed state. Based on this property, we propose an inverse-squeezing conditional pulse-nulling (IS-CPN) receiver. In the ideal case, inverse squeezing maps S-PPM into an equivalent coherent-state PPM signal with a large pulse energy, leading to a closed-form expression for the receiver error probability. We further analyze IS-CPN under common phase diffusion using a finite-path MAP formulation with phase-averaged likelihoods. Numerical results show that IS-CPN outperforms conventional CPN under the same energy constraint and remains advantageous under phase noise and finite photon-number resolution. These results demonstrate that combining squeezed-state modulation with inverse-squeezing conditional nulling can improve photon-efficient optical communication.

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Enhao Bai, Fengkai Sun, Tianyi Wu, Huankai Zhang, Jian Peng, Chen Dong, Zhenrong Zhang. 2026-06-30. Inverse-squeezing receivers for squeezed-state pulse-position modulation under ideal and phase-diffusion conditions. https://arxiv.org/abs/2606.31541

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