SYSTEM FOR AMPLIFYING OPTICAL SIGNAL, TRANSMISSION SYSTEM WITH DISPERSION MAP, AND ERBIUM DOPED FIBER AMPLIFIER (EDFA)

摘要

PPROBLEM TO BE SOLVED: To provide a hybrid Raman EDFA which can obtain a substantially flat gain in a wide band. PSOLUTION: The hybrid Raman EDFA provides gain equalization over the C-band and L-band. The EDFA has a Raman section producing a Raman gain, and an EDFA section producing an EDFA gain complimenting the Raman gain. The EDFA section includes a highly inverted, single-stage EDFA to produce a complimenting EDFA gain shape. The EDFA section includes a high return loss termination located after an erbium fiber to receive an unabsorbed pump power. A plurality of hybrid Raman-EDFAs are connected in an amplifier chain in a transmission system. The transmission system provides a dispersion map including regular composite fiber spans followed by at least one compensating span of negative dispersion fibers. The Raman sections of the hybrid Raman-EDFAs are coupled to a negative dispersion fiber in the transmission system. PCOPYRIGHT: (C)2008,JPO&INPIT