Title :
Gain monitoring of erbium-doped fiber amplifiers by detecting spontaneous emission
Author :
Masuda, Hiroji ; Aida, Kazuo
Author_Institution :
NTT Transmission Syst. Labs., Kanagawa, Japan
Abstract :
Gain monitoring by detecting the spontaneous emission (SE) emitted by 0.98- mu m laser diode (LD) pumped erbium-doped fiber amplifiers was investigated using three erbium-doped fibers (EDF´s) with different absorption coefficients at 1.55 mu m ( alpha ). Unfavorable 0.98- mu m scattered light was observed and removed by an optical filter. The minimum gain accuracy was less than +or-0.21 dB for EDF-b ( alpha =1.5 dB/m) with launched pump powers (P/sub p/) from 10 to 30 mW. The minimum gain reproducibility over a 9-h period was +or- 0.015 dB for EDF-a ( alpha =3.3 dB/m) at P/sub p/=20 mW.<>
Keywords :
erbium; fibre lasers; laser variables measurement; optical pumping; 1.55 mum; 10 to 30 mW; Er doped fibre amplifier; absorption coefficients; erbium-doped fiber amplifiers; gain monitoring; laser diode; laser pumping; launched pump powers; minimum gain accuracy; minimum gain reproducibility; optical filter; scattered light; spontaneous emission; Absorption; Diode lasers; Erbium-doped fiber amplifier; Laser excitation; Light scattering; Monitoring; Optical filters; Optical scattering; Reproducibility of results; Spontaneous emission;
Journal_Title :
Photonics Technology Letters, IEEE
