The influence of the degree of coherence of a semiconductor laser on the statistic of the backscattered intensity in a single-mode optical fiber

Alekseev, Alexey E.; Tezadov, Ya. A.; Потапов, В. Т.

doi:10.1134/s106422691112014x

Cited by 11 publications

(19 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Therefore the corresponding bandwidth threshold turns out to be exactly 1/τ rect . Note however that the visibility of φOTDR traces may also depend on other factors, such as the presence of modulation instability [15] and the degree of coherence of the laser [18]. Hence, the visibility threshold may vary under non-optimized experimental conditions, but its corresponding bandwidth should always be 1/τ rect .…”

Section: A Trace Visibilitymentioning

confidence: 99%

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry With Direct Detection

Soto

Zhang

et al. 2020

J. Lightwave Technol.

View full text Add to dashboard Cite

The spectral properties of the Rayleigh backscattered traces measured by a phase-sensitive optical time-domain reflectometer (φOTDR) with direct detection are theoretically and experimentally analyzed. The spectrum of the measured φOTDR signal is found to be strictly dependent on the spectral shape of the probing optical pulse. Furthermore, the visibility, spatial resolution, fading rate, and correlation spectrum of the traces are analyzed using different detection bandwidths. Results point out that the quality of φOTDR traces and target spatial resolution are secured only if the electrical bandwidth of the photodetector is broad enough to cover at least 80% of the total power contained in the electrical spectral density function of the measured trace. This means that in the case of using direct detection of the Rayleigh backscattered light induced by rectangular-shaped optical pulses, the minimum bandwidth required for a proper detection of the traces is equal to the reciprocal of the pulse temporal width (which is larger than the pulse spectral width). Although the theoretical analysis and numerical simulations are here experimentally validated for rectangular and sinc-shaped optical pulses, the results and methodology presented in this article can be applied to optimize the direct-detection bandwidth of φOTDR sensors using any optical pulse shape.

show abstract

Section: A Trace Visibilitymentioning

confidence: 99%

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry With Direct Detection

Soto

Zhang

et al. 2020

J. Lightwave Technol.

View full text Add to dashboard Cite

show abstract

“…where A is the perturbation amplitude, T s is the time moment relation to the impact of the perturbation, τ s is the period of perturbation induced oscillations, τ a is the damping constant. By substituting (11) to (9), we obtain periodical phase oscillations in the following form This expression being substituted in Eq. (13) allows one to obtain the signal detected by the system in the case of absence of the background.…”

Section: Numerical Simulationsmentioning

confidence: 99%

Section: Numerical Simulationsmentioning

confidence: 99%

“…In general, quality of sensing systems for remote monitoring of extended objects is determined by its ability to detect perturbations caused by an activity near the sensor fiber within a background, where this background is formed both by external noises (e.g., seismic noises) and self-noises of the system. In order to maximize the rate of recognized (i.e., detected and classified) perturbations, Φ-OTDR based sensors have been studied throughout via numerical simulations [10][11][12][13][14][15][16].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of the Laser Frequency Drift in Phase-Sensitive Optical Time Domain Reflectometry

Zhirnov¹,

Stepanov²,

Chernutsky³

et al. 2019

Opt. Spectrosc.

View full text Add to dashboard Cite

The present work studies the influence of laser frequency drifts on operating of phase-sensitive optical time-domain reflectometry (Φ-OTDR) fiber sensors. A mathematical model and numerical simulations are employed to highlight the influence of frequency drifts of light sources on two characteristic scales: large-time (minutes) and short-time (milliseconds) frequency drifts. Numerical simulation results are compared with predictions given by the fluctuation ratio coefficient (FRC), and they are in a qualitative agreement. In addition to qualitative criteria for light sources given by the FRC, quantitive requirements for optimal light sources for Φ-OTDR sensors are obtained. Numerical simulation results are verified by comparison with experimental data for three significantly different types of light source.

show abstract

“…В целом, качество сенсорных систем для удаленного контроля протяженных объектов определяется их способностью обнаруживать возмущения, вызванные активностью вблизи волокна на фоне, формируемом как внешними шумами (например, сейсмическими), так и собственными шумами системы. Для изучения их влияния датчики на основе Ph-OTDR исследовались также на базе численного моделирования [10,[14][15][16][17][18][19][20].…”

Section: Introductionunclassified

Влияние Дрейфа Частоты Лазера В Фазочувствительной Рефлектометрии

Жирнов¹,

Степанов²,

Чернуцкий³

et al. 2019

Журнал Технической Физики

View full text Add to dashboard Cite

The influence of the laser frequency drift on the operation of phase-sensitive optical time domain reflectometry (φ-OTDR) systems is considered. Theoretical results based on a new numerical φ-OTDR model demonstrating the influence of the laser frequency instability on a signal are reported. This model is verified based on experimental data. It has been used to calculate the signal-to-noise ratio (SNR) of the system for different parameters of the laser source stability. As a result, quantitative requirements for lasers used in φ-OTDR systems are formulated.

show abstract

The influence of the degree of coherence of a semiconductor laser on the statistic of the backscattered intensity in a single-mode optical fiber

Cited by 11 publications

References 7 publications

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry With Direct Detection

Spectral Properties of the Signal in Phase-Sensitive Optical Time-Domain Reflectometry With Direct Detection

Influence of the Laser Frequency Drift in Phase-Sensitive Optical Time Domain Reflectometry

Влияние Дрейфа Частоты Лазера В Фазочувствительной Рефлектометрии

Contact Info

Product

Resources

About