EQUALIZATION OF NONUNIFORM EDFA GAIN USING A FIBER-LOOP MIRROR

We have experimentally demonstrated cascaded EDFA gain equalization us ing a fiber-loop mirror (FLM) acting as a linear wavelength filter. By changing the intra-loop polarization, the FLM passband center wavelen gth can be tuned. Additionally, there is some ability to change the ba ndwidth and filter slope of the FLM. The FLM is used to equalize the n onuniform gain of a cascade of EDFA's. After 1500 km, the power differ ential is reduced from 30 to 2 dB for three WDM channels covering a 9- nm wavelength range.