Computer-aided analysis of transients in fiber lasers and gain-clamped fiber amplifiers in ring and line configurations through a circuit simulator精品.pdfVIP

15 August 2002 Optics Communications 209 (2002) 427–436 /locate/optcom Computer-aided analysis of transients in fiber lasers and gain-clamped fiber amplifiers in ring and line configurations through a circuit simulator * Cheng-Kuang Liu , Jau-Ji Jou, Shien-Kuei Liaw, Hsiu-Chih Lee Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan RO Received 7 December 2001; received in revised form 10 June 2002; accepted 26 June 2002 Abstract The authors have presented unified partitioned electrical circuit models of erbium-doped fiber (EDF) systems, including fiber lasers and fiber amplifiers in ring and line configurations. Results are accurately demonstrated of the relaxation oscillation due to the adding or dropping of wavelength-division multiplexing (WDM) channels in a gain- clamped erbium-doped-fiber amplifier (EDFA). The turn-on transients and the effect of feedback in an erbium-doped fiber laser (EDFL) are shown. The effects of fiber grating reflectivity and EDF length on fiber lasers are also presented. They are informative and convenient for the designs of EDFA systems. 2002 Elsevier Science B.V. All rights reserved. Keywords: Fiber laser; Fiber amplifier; WDM; Electrical circuit model 1. Introduction Wavelength-division multiplexing (WDM) and rare-earth-doped fiber amplifing are key technol- Erbium-doped fiber lasers (EDFLs) have been ogies in high-speed and large capacity telecom- extensively investigated for ma