<title>Distributed temperature sensors for single-mode fibers</title>

Abstract

Single mode fibers are being installed in nearly all communication lines. For the purpose of maintenance and observation of line, data of the installed fiber condition is needed. Distributed temperature sensing for single mode fiber is expected in this field. Special wavelength light sources are necessary to measure the temperature distribution by Raman ratiomelry because of avoiding the single mode fiber's cut-off wavelength Distributed temperature sensing of the single mode fiber is perceived using fiber Raman laser. Fiber Raman laser is pumped by the LD pumped solid state laser source. l400nm pulse light is coupled into a single mode fiber, and the 1320 Anti-Stokes and l500nm Stokes light are detected to calculate the temperature. Temperature accuracy is with the average time of 3mm and maximum measurable range is 3 km.

Distributed Temperature Sensing: Review of Technology and Applications

“…The intensity of the Anti-Stokes band is temperature dependent, while the Stokes band is temperature insensitive. The ratio of the Anti-Stokes and the Stokes light intensities provides the local temperature measurement [5]. This is shown in Fig.…”

Distributed fiber optic sensing over readily available telecom fiber networks

“…DFOS can refer to several different types of sensing mechanisms depending on the way the fiber cable is illuminated, and which properties of the backscattered light is investigated. The three major DFOS systems are Distributed Temperature Sensing (DTS), Distributed Vibration Sensing (DVS), and Distributed Acoustic Sensing (DAS) systems [1][2][3].…”

Mass Flow Monitoring by Distributed Fiber Optical Temperature Sensing

“…The most suitable distributed fiber optical temperature sensing methods are Raman optical time domain reflectometry (ROTDR) [13,14,15,16,17], Brillouin optical time domain analysis (BOTDA) [18,19,20], phase optical time domain reflectometry (Φ-OTDR) [21], and optical Fourier domain reflectometry (OFDR) [22]. Compared to Raman sensors, BOTDA can inherently provide more accurate measurements and achieve longer sensing distances [23].…”