Physics Journal of the Indonesian Physical Society
GAIN IMPROVEMENT IN L-BAND ERBIUM-DOPED FIBER AMPLIFIER WITH C-BAND ASE INJECTION
Sulaiman Wadi Harun and H. Ahmad
Photonics Laboratory, Department of Physics, University of Malaya, 50603 Kuala Lumpur, Malaysia
The gain improvement technique for long wavelength band erbium doped fiber amplifier (L-band EDFA) by injecting conventional band (C-band) amplified spontaneous emission (ASE) is demonstrated. It uses an optical circulator and broadband fiber Bragg grating (FBG) to route C-band ASE from a C-band EDFA into a single stage L-band EDFA. Injection of a C-band ASE improves a small signal gain with a negligible noise figure penalty. The small signal gain is improved from 16.1dB to 19.5dB for 1580nm signal at pump power of 92mW, compared to an amplifier without ASE injection. The maximum gain improvement of 6.9dB was obtained at input signal wavelength of 1568nm, while signal and pump powers were fixed at -30dBm and 92mW, respectively. These results show that the C-band ASE injection technique can be used for gain improvement in L-band EDFA.