基于差分格雷脉冲编码的长距离高空间分辨率拉曼分布式光纤传感技术研究

doi:10.16553/j.cnki.issn1000-985x.2026.0089

摘要/Abstract

摘要： 针对传统拉曼分布式光纤传感（RDTS）技术中长距离探测与高空间分辨率难以兼顾的技术瓶颈，本文提出了一种基于差分格雷脉冲编码（DPG-codes）的分布式传感方案。该技术结合了差分格雷脉冲编码增益与差分处理机制，通过利用格雷互补序列优异的自相关特性，在不诱发光纤非线性效应的前提下，大幅提升了系统注入光能量与远端散射信号信噪比。系统向传感光纤依次注入由长、短两种脉宽独立调制的格雷脉冲编码序列，并对解码后的背向拉曼散射信号进行差分运算，获得了等效脉宽为4 ns的高空间分辨率拉曼散射响应。数值仿真结果表明，与传统技术相比，采用DPG-codes方案，光纤末端的信噪比提升了8.89 dB，系统的温度分辨率由33.06 ℃提升至3.54 ℃。最终在150.0 km的传感距离下，实现了0.40 m的高空间分辨率传感性能。

关键词: 分布式光纤传感; 拉曼散射; 传感距离; 空间分辨率; 脉冲编码

Abstract: To address the trade-off between long sensing distance and high spatial resolution in conventional Raman distributed temperature sensing （RDTS）， this paper presents a sensing scheme based on differential pulse Golay codes （DPG-codes）. The approach integrates the coding gain of differential pulse Golay codes with a differential processing mechanism. By exploiting the excellent autocorrelation characteristics of Golay complementary sequences， the launched optical energy and the far-end signal-to-noise ratio are substantially increased， all while avoiding nonlinear effects within the fiber. In the proposed scheme， Golay-coded sequences independently modulated by long and short pulse widths are sequentially injected into the sensing fiber. A differential operation is then performed on the decoded backscattered Raman signals， yielding a Raman scattering response that corresponds to an equivalent pulse width of just 4 ns and thereby delivers high spatial resolution. Numerical simulation results show that， relative to conventional techniques， the DPG-codes scheme raises the signal-to-noise ratio at the fiber end by 8.89 dB and improves the temperature resolution from 33.06 ℃ to 3.54 ℃. Ultimately， a spatial resolution of 0.40 m is achieved across a sensing distance of 150.0 km.

Key words: distributed optical fiber sensing; Raman scattering; sensing distance; spatial resolution; pulse coding

中图分类号:

O436

王佳乐, 李健, 张帆, 李璐磊, 王日龙, 张明江. 基于差分格雷脉冲编码的长距离高空间分辨率拉曼分布式光纤传感技术研究[J]. 人工晶体学报, 2026, 55(8): 1213-1221.

WANG Jiale, LI Jian, ZHANG Fan, LI Lulei, WANG Rilong, ZHANG Mingjiang. Long-Range, High-Spatial-Resolution Raman Distributed Optical Fiber Sensing Based on Differential Pulse Golay Coding[J]. Journal of Synthetic Crystals, 2026, 55(8): 1213-1221.

图/表 9

表1 代表性RDTS方案性能对比

Table 1 Performance comparison of representative RDTS schemes

技术方案	传感距离	空间分辨率	温度分辨率
锁模飞秒脉冲方案	3.0 m	0.01 m	—
增强型抗失真编码与波形重构方案	70.0 km	1.58 m	5.39 ℃
混沌非对称脉冲对相关增强方案	10.0 km	0.30 m	—
渐变折射率少模光纤方案	25.0 km	1.10 m	1.0 ℃
方波宽度啁啾脉冲压缩方案	45.0 km	0.50 m	—
DPG-codes方案	150.0 km	0.40 m	3.54 ℃

图1 DPG-codes方案实验装置图

Fig.1 Experimental setup of the DPG-codes scheme

图2 差分格雷脉冲编码方案时序图

Fig.2 Timing diagram of the differential Golay pulse coding scheme

表2 DPG-codes数值模型仿真参数

Table 2 Parameters related to DPG-codes numerical modeling simulation

Parameter	Physical meaning	Value
$K a s$	Raman anti-Stokes signal coefficient	3.066 41×10^-9
$n$	Refractive index of the fiber	1.5
$λ$	Raman anti-Stokes signal wavelength/nm	1 450
$Δ ν$	Raman frequency shift/THz	13.2
$l$	Length of codes/bit	128
$α 0 + α a s$	Transmission loss/（dB·km^-1）	1.18
$T 0$	Room temperature/℃	20
$T$	FUT temperature/℃	90
$τ W$	Long pulse width/ns	10
$τ N$	Short pulse width/ns	6

表2 DPG-codes数值模型仿真参数

Table 2 Parameters related to DPG-codes numerical modeling simulation

Parameter	Physical meaning	Value
$K a s$	Raman anti-Stokes signal coefficient	3.066 41×10^-9
$n$	Refractive index of the fiber	1.5
$λ$	Raman anti-Stokes signal wavelength/nm	1 450
$Δ ν$	Raman frequency shift/THz	13.2
$l$	Length of codes/bit	128
$α 0 + α a s$	Transmission loss/（dB·km^-1）	1.18
$T 0$	Room temperature/℃	20
$T$	FUT temperature/℃	90
$τ W$	Long pulse width/ns	10
$τ N$	Short pulse width/ns	6

图3 基于单脉冲和DPG-codes方案的信噪比

Fig.3 SNR based on single pulse and DPG-codes scheme

图4 基于单脉冲和DPG-codes方案的温度解调曲线

Fig.4 Temperature demodulation curve based on single pulse and DPG-codes scheme

图5 基于单脉冲和DPG-codes方案的温度分辨率

Fig.5 Temperature resolution based on single pulse and DPG-codes scheme

图6 基于DPG-codes方案的空间分辨率

Fig.6 Spatial resolution based on DPG-codes scheme

图7 空间分辨率测量结果

Fig.7 Spatial resolution measurement result

参考文献 22

[1]	XU Z G， LING J M， YE W， et al. Spatial resolution optimization technology of Raman OTDR using variable sampling rate［J］. IEEE Sensors Journal， 2023， 23（10）： 10500-10508. DOI URL
[2]	SOTO M A， RAMÍREZ J A， THÉVENAZ L. Intensifying the response of distributed optical fibre sensors using 2D and 3D image restoration［J］. Nature Communications， 2016， 7： 10870. DOI PMID
[3]	许鹏柏，王小龙，温坤华，等. 基于BOTDA的分布式光纤高温传感研究（特邀）［J］. 红外与激光工程， 2022， 51（10）： 20220549.
	XU P B， WANG X L， WEN K H， et al. Distributed fiber high-temperature sensing based on BOTDA （invited）［J］. Infrared and Laser Engineering， 2022， 51（10）： 20220549 （in Chinese）. DOI URL
[4]	李　硕，王纪强，高忠国，等. 基于拉曼信号分段重构的分布式光纤测温空间分辨率提升研究［J］. 红外与激光工程， 2023， 52（10）： 20230076.
	LI S， WANG J Q， GAO Z G， et al. Research on spatial resolution improvement of distributed optical fiber temperature measurement based on Raman signal segmentation and reconstruction［J］. Infrared and Laser Engineering， 2023， 52（10）： 20230076 （in Chinese）. DOI URL
[5]	GAO S F， WANG Y Y， DING W， et al. Conquering the Rayleigh scattering limit of silica glass fiber at visible wavelengths with a hollow-core fiber approach［J］. Laser & Photonics Reviews， 2020， 14（1）： 1900241. DOI URL
[6]	ZHANG Z L， LU Y G， PENG J Q， et al. Simultaneous measurement of temperature and acoustic impedance based on forward Brillouin scattering in LEAF［J］. Optics Letters， 2021， 46（7）： 1776-1779. DOI PMID
[7]	ZHANG Z S， WU H， ZHAO C， et al. High-performance Raman distributed temperature sensing powered by deep learning［J］. Journal of Lightwave Technology， 2021， 39（2）： 654-659. DOI URL
[8]	LI J， ZHANG M J. Physics and applications of Raman distributed optical fiber sensing［J］. Light： Science & Applications， 2022， 11： 128.
[9]	LI J， ZHANG Q， YU T， et al. R-DTS with heat transfer functional model for perceiving the surrounding temperature［J］. IEEE Sensors Journal， 2020， 20（2）： 816-822. DOI URL
[10]	WANG Y H， ZHENG S S， YANG W M， et al. In situ Raman spectroscopy reveals the structure and dissociation of interfacial water［J］. Nature， 2021， 600（7887）： 81-85. DOI
[11]	OSOSKOV Y Z， CHERNUTSKY A O， DVORETSKIY D A， et al. Fiber optic Raman distributed temperature sensor based on an ultrashort pulse mode-locked fiber laser［J］. Optics and Spectroscopy， 2019， 127（4）： 664-668. DOI
[12]	PARK J， BOLOGNINI G， LEE D， et al. Raman-based distributed temperature sensor with simplex coding and link optimization［J］. IEEE Photonics Technology Letters， 2006， 18（17）： 1879-1881. DOI URL
[13]	WANG Q L， BAI Q， LIANG C S， et al. Random coding method for SNR enhancement of BOTDR［J］. Optics Express， 2022， 30（7）： 11604. DOI PMID
[14]	ROSOLEM J B， BASSAN F R， DE FREITAS D E， et al. Raman DTS based on OTDR improved by using gain-controlled EDFA and pre-shaped simplex code［J］. IEEE Sensors Journal， 2017， 17（11）： 3346-3353. DOI URL
[15]	ZHANG F， LI J， LI L L， et al. 70 km long-range Raman distributed optical fibre sensing through enhanced anti-distortion coding and waveform reconstruction［J］. Nature Communications， 2026， 17： 676. DOI
[16]	WANG C Y， LI J， ZHOU X X， et al. Chaos Raman distributed optical fiber sensing［J］. Light： Science & Applications， 2023， 12： 213.
[17]	FAN B W， LI J， CHENG Z J， et al. Realizing submeter spatial resolution for Raman distributed fiber-optic sensing using a chaotic asymmetric paired-pulse correlation-enhanced scheme［J］. Photonics Research， 2024， 12（10）： 2365. DOI URL
[18]	LIU Y P， MA L， YANG C， et al. Long-range Raman distributed temperature sensor with high spatial and temperature resolution using graded-index few-mode fiber［J］. Optics Express， 2018， 26（16）： 20562. DOI PMID
[19]	WU H， DU H Z， ZHAO C， et al. 24 km high-performance Raman distributed temperature sensing using low water peak fiber and optimized denoising neural network［J］. Sensors， 2022， 22（6）： 2139. DOI URL
[20]	LIU X， JIE R M， BERA S， et al. High-speed and high-resolution YAG fiber based distributed high temperature sensing system empowered by a 2D image restoration algorithm［J］. Optics Express， 2023， 31（4）： 6170. DOI PMID
[21]	LI J， ZHOU X X， XU Y， et al. Slope-assisted Raman distributed optical fiber sensing［J］. Photonics Research， 2022， 10（1）： 205. DOI URL
[22]	FAN B W， LI J， ZHANG X Y， et al. 45 km ROTDR with 0.5 m/0.11 ℃ via complex-domain square-wave width-chirp pulse compression［J］. Light： Science & Applications， 2026， 15： 175.