Simplified BOTDA System Based on Direct Modulation of a Laser Diode With an Extended Measurement Range

Author

Jun Gi Hong ; Kwang Yong Song

Author_Institution

Dept. of Phys., Chung-Ang Univ., Seoul, South Korea

Volume

33

Issue

10

fYear

2015

fDate

May15, 15 2015

Firstpage

1979

Lastpage

1984

Abstract

We demonstrate a simplified Brillouin optical time-domain analysis system based on direct current modulation of a laser diode which is configured and optimized for long-range measurement. A precompensated low-frequency RF wave is applied for time-division generation of Brillouin pump and probe waves without using any microwave device. Low-speed frequency dithering of the laser diode is additionally applied for the suppression of the coherent noise originating from Rayleigh scattering of the leakage probe wave. In experiments, distributed measurements of Brillouin frequency shift along a 25 km single-mode fiber are presented with a spatial resolution of 1.2 m and measurement accuracy (σ) of 0.45 MHz, respectively.

Keywords

Brillouin spectra; Rayleigh scattering; laser noise; laser variables measurement; light coherence; measurement by laser beam; optical fibre testing; optical modulation; semiconductor lasers; Brillouin frequency shift; Brillouin pump; Rayleigh scattering; coherent noise suppression; direct current modulation; distance 25 km; extended measurement range; laser diode; leakage probe wave; low-frequency RF wave precompensation; low-speed frequency dithering; probe waves; simplified BOTDA system; simplified Brillouin optical time-domain analysis system; single-mode fiber; spatial resolution; time-division generation; Frequency measurement; Frequency modulation; Optical fibers; Optical pumping; Probes; Scattering; Brillouin scattering; Modulation; Optical fiber measurement; modulation; optical fiber measurement;

fLanguage

English

Journal_Title

Lightwave Technology, Journal of

Publisher

ieee

ISSN

0733-8724

Type

jour

DOI

10.1109/JLT.2015.2394433

Filename

7021950