发表机构
School of Electronic and Information Engineering, Soochow University（苏州大学电子与信息工程学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究针对光纤ISAC的关键挑战，提出连续DMT框架，实现同一波形同时支持IM/DD通信与DAS，经10km光纤实验，两种DMT方案定位精度高、相位恢复相关性好且通信无错码。
AI 中文摘要
光纤集成感知与通信（ISAC）的一项关键挑战是使承载有效载荷的波形本身同时支持两种功能，无需单独的感知波形或仅用于感知的静默间隔。我们提出了一种具有两种波形模式的连续离散多音（DMT）框架，其中同一承载有效载荷的波形支持前向强度调制/直接检测（IM/DD）通信和后向分布式声学传感（DAS）。统一的相位敏感光时域反射计（φ-OTDR）模型将分布式瑞利后向散射表示为有限记忆感知多径信道。该模型表明，传统的脉冲等待型φ-OTDR需要往返时间尺度的静默间隔来隔离连续回波，而实际匹配滤波（MF）脉冲压缩中的非零峰外样本会导致空间符号间干扰（ISI）。相反，连续DMT保留叠加回波，并通过已知波形信道重构分离距离单元贡献。循环前缀DMT（CP-DMT）使用全记忆循环前缀和单抽头频域均衡（FDE）；在足够的循环前缀和理想全频点反转条件下，它消除了MF相关引起的空间ISI。无循环前缀DMT（NoCP-DMT）将正则化最小二乘（LS）应用于长记忆线性卷积，以在更高的接收机复杂度下避免循环前缀。在10公里光纤链路上的实验中，我们定位了由压电换能器（PZT）施加在5.071公里附近的600赫兹扰动，并恢复了差分相位，CP-DMT和NoCP-DMT的相关系数分别为0.989和0.987。在2伏和1伏的PZT驱动电平下，十次记录的定位标准偏差分别为0.16/0.11米和0.18/0.38米。对应的IM/DD误差矢量幅度值在4.80%至5.00%之间，未观察到误码。
英文摘要
A key challenge in fiber-optic integrated sensing and communication (ISAC) is to make the payload-bearing waveform itself serve both functions without a separate sensing waveform or sensing-only silent interval. We propose a continuous discrete multitone (DMT) framework with two waveform modes, in which the same payload-bearing waveform supports forward intensity-modulation/direct-detection (IM/DD) communication and backward distributed acoustic sensing (DAS). A unified phase-sensitive optical time-domain reflectometry (ϕ-OTDR) model represents distributed Rayleigh backscattering as a finite-memory sensing multipath channel. It shows that conventional pulse-and-wait ϕ-OTDR requires a round-trip-time-scale silent interval to isolate successive returns, while nonzero off-peak samples in practical matched-filter (MF) pulse compression cause spatial intersymbol interference (ISI). Continuous DMT instead retains superposed returns and separates range-cell contributions through known-waveform channel reconstruction. Cyclic-prefix DMT (CP-DMT) uses a full-memory CP and one-tap frequency-domain equalization (FDE); under sufficient-CP and ideal full-bin inversion conditions, it eliminates MF-correlation-induced spatial ISI. Cyclic-prefix-free DMT (NoCP-DMT) applies regularized least squares (LS) to the long-memory linear convolution, avoiding the CP at higher receiver complexity. Experiments over a 10-km fiber link localize a 600-Hz disturbance applied by a piezoelectric transducer (PZT) near 5.071 km and recover gauge-differential phase with correlations of 0.989 and 0.987 for CP-DMT and NoCP-DMT, respectively. At 2- and 1-V PZT drive levels, the ten-record localization standard deviations are 0.16/0.11 m and 0.18/0.38 m, respectively. The corresponding IM/DD error vector magnitude values range from 4.80% to 5.00%, with no bit errors observed.
CommentsThis manuscript has been submitted for consideration for publication
