| 摘要 |
PROBLEM TO BE SOLVED: To apply an amplifier to an optical communication system transmitting the both up and down signals in a single transmission line and to enable the spectrum spread of an optical fiber for transmission and the compensation of propagation loss. SOLUTION: This amplifier is provided with an optical circulator 3 provided with first, second, third and fourth ports A, B, C and D. Each of the second and fourth ports B and D is connected with exciting light introduction means 30a and 30b, erbium dope fibers(EDF) 4a and 4b, exciting light reflectors 6a and 6b, dispersion compensation optical filters(DCF) 5a and 5b and optical reflection means 8a and 8b in order. An upward signal is reciprocatively propagated in order of the second port → the EDF 4a → the DCF 5a → the DCF 5a → the EDF 4a A down signal is reciprocatively propagated in order of the fourth port D → the EDF 4b → the DCF 5b → the DCF 5b → the EDF 4b. The dispersion compensation by the DCF and the optical amplification by the EDF for every signal are efficiently performed. |
