Tilt control through optical pump power adjustment

摘要

The adjustment of tilt in an optical signal path of a repeater. The repeater includes an optical pump that optically powers a rare-Earth doped fiber amplifier, which amplifies the optical signal. The optical signal path also includes Raman gain stage implemented in a previous optical fiber span in the optical signal path, and which contributes tilt with respect to wavelength. Adjusting the Raman gain and/or the rare-Earth doped gain also adjusts the combined tilt contributed by these gain stages. However, the rare-Earth doped gain operates at least partially in the saturated regime, thereby stabilizing the gain at the output of the rare-Earth doped amplifier. Thus tilt control may be employed by adjusting optical pump power with reduced effect on overall gain.

主权项

1. A repeater comprising:
a rare-Earth doped fiber amplifier configured to amplify an optical signal while operating at least partially in a gain saturation regime; a doped fiber amplifier optical pump configured to supply optical pump power to the rare-Earth doped fiber amplifier; a Raman pump configured to provide Raman amplification to the optical signal; a tilt sensor configured to detect tilt of the optical signal downstream of the rare-Earth doped fiber amplifier in an optical signal path; and a tilt adjustment controller configured to adjust the tilt of the optical signal by controlling at least one of: (i) the optical pump power supplied by the doped fiber amplifier optical pump or (ii) Raman pump power supplied by the Raman pump.