Physics Journal of the Indonesian Physical Society
DOUBLE-PASS GAIN CLAMPED L-BAND EDFA WITH ENHANCED GAIN AND NOISE FIGURE
S. W. Harun1, N. Md Samsuri2, P. Poopalan2 and H. Ahmad2
1Faculty of Engineering, Multimedia University, Jalan Multimedia, 63100 Cyberjaya, Selangor, Malaysia
2Photonics Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia
A gain-clamped double-pass L-band EDFA with high clamped-gain and low noise figure is demonstrated using a ring laser. The broadband FBG operating at L-band region is used to retro-pass the test signal back into the system for gain enhancing. A short length of forward pumped EDF is incorporated in front of the double-pass amplifier to achieve a low noise figure. The gain clamping is achieved by routing the backward ASE into the feedback loop to create ring laser. The gain is clamped at 26.8 dB from -40 to -16 dBm with a gain variation of less than „b0.1 dB at variable optical attenuator setting of 0 dB. The corresponding noise figure varies from 5.0 to 5.3 dB, which is relatively lower compared with that of conventional double-pass amplifier.