Title :
Pencil-lead-break transient detecting by phase- optical time domain reflectometer based on coherent detecting
Author_Institution :
Key Lab. of In-fiber Integrated Opt., Harbin Eng. Univ., Harbin, China
Abstract :
Pencil-lead-break transient detecting is demonstrated by phase- optical time domain reflectometer based on coherent detecting and data processing. By using coherent detecting technology, combined with Erbium-doped Optical Fiber Amplifier and high power load Acousto-optical Modulators (AOM), we improves signal detecting sensitive and Signal-noise-ratio by 2~3dB coherent detection advantage over direct detection of phase-OTDR. Location of pencil-lead-break transient signal was detected with higher spatial resolution in time domain by averaged traces transiently. Using varying power with time of the location, frequency information can be obtained by fast Fourier transforms (FFT) analyzer. With loop geometry fiber, as short as 0.25cm fiber can give effective signal over 12-km long single-mode fiber and as high as 50 kHz frequency component can be detected.
Keywords :
acousto-optical modulation; erbium; fast Fourier transforms; fibre optic sensors; optical fibre amplifiers; optical signal detection; optical time-domain reflectometry; AOM; FFT analyzer; coherent detection; data processing; distance 12 km; erbium-doped optical fiber amplifier; fast Fourier transforms; frequency 50 kHz; frequency information; high power load acousto-optical modulators; loop geometry fiber; noise figure 2 dB to 3 dB; pencil-lead-break transient detection; phase-OTDR; phase-optical time domain reflectometer; signal detection; signal-noise-ratio; single-mode fiber; spatial resolution; Optical fiber sensors; Optical fibers; Optical interferometry; Optical reflection; Time-domain analysis; coherent detection; pencil-lead-break; vibration;
Conference_Titel :
Optoelectronics and Microelectronics (ICOM), 2013 International Conference on
Conference_Location :
Harbin
Print_ISBN :
978-1-4799-1214-8
DOI :
10.1109/ICoOM.2013.6626534
