Claims
- 1. An apparatus for compensating for both expansion-type and compression-type gain distortion products resulting from the interaction of a laser and an erbium-doped fiber optical amplifier (EDFA) comprising:
- a predetermined length of erbium-doped absorption fiber having an absorption profile as a function of wavelength which is equal in magnitude and opposite in phase to the variation from the mean gain profile of the EDFA; and
- means for coupling said predetermined length of said erbium-doped absorption fiber between the optical output of said laser and the optical input of said optical amplifier.
- 2. An apparatus according to claim 1 wherein said predetermined length of said erbium-doped fiber comprises a length in meters approximately equal to the average variation of EDFA gain in dB from a mean value of said gain divided by the coefficient of absorption in dB/m of the erbium-doped absorption fiber.
- 3. An apparatus according to claim 1 comprising an optical filter coupled between said absorption fiber and said EDFA.
Parent Case Info
This application is a divisional of Ser. No. 07/787,830, filed Nov. 5, 1991, now U.S. Pat. No. 5,243,613.
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3774120 |
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4979234 |
Agrawal et al. |
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Divisions (1)
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Number |
Date |
Country |
Parent |
787830 |
Nov 1991 |
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