Patent ID: 9025955
Filing Date: 2015-05-05
Classification: H01S,H04B,H04J

Abstract:
1. An amplification apparatus provided between an optical line terminal (OLT) and an optical network unit (ONU), the amplification apparatus comprising: a circulator configured to output light incident on a first terminal from a second terminal, light incident on the second terminal from a third terminal, light incident on the third terminal from a fourth terminal, and light incident on the fourth terminal from the first terminal and to receive, at the first terminal, first signal light transmitted from the OLT to the ONU and first light having a predetermined wavelength different from a wavelength of the first signal light and, at the third terminal, second signal light transmitted from the ONU to the OLT and second light having the predetermined wavelength, the second signal light having a wavelength different from the wavelength of the first signal light and different from the predetermined wavelength; a first reflector configured to reflect the light output from the second terminal and to output the reflected light back to the second terminal; a first optical amplifier configured to be provided between the second terminal and the first reflector and to have an amplification band characteristic of amplifying at least the first signal light; a second reflector configured to reflect the light output from the fourth terminal and to output the reflected light back to the fourth terminal; a second optical amplifier configured to be provided between the fourth terminal and the second reflector and to have an amplification band characteristic of amplifying the second signal light without amplifying the second light having the predetermined wavelength; and a first partial reflector configured to have a wavelength transmission characteristic of propagating, in the light output from the fourth terminal, the second signal light and outputting the second signal light to the sound optical amplifier while reflecting the second light having the predetermined wavelength and outputting the reflected second light back to the fourth terminal.