Double pass L-band EDFA incorporating band pass filter

A new double pass long wavelength band erbium-doped fiber amplifier (L-band EDFA) system with improved gain and noise figure is demonstrated by incorporating a band-pass filter. Compared to the previous double pass amplifier, the proposed amplifier provides a maximum gain enhancement of 1.5 dB with reduction of noise figure by 1.2 dB at a pump power of 83 mW. The double pass system with BPF can give an equal value of gain as single pass system, but using only 62% of pump power.