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.