Patent ID: 6212311
Filing Date: 2001-04-03
Classification: H04B

Abstract:
A light signal transmission system for maintaining a desired light signal amplification level between a first terminal and a second terminal comprising:a first optical fiber transmitting the light signal from the first terminal to the second terminal and a second optical fiber transmitting the light signal from the second terminal to the first terminal, the first optical fiber having a first amplification fiber and the second optical fiber having a second amplification fiber;a first excitation light source supplying excitation light to the second optical amplification fiber through the second optical fiber from the first terminal;a second excitation light source supplying excitation light to the first optical amplification fiber through the first optical fiber from the second terminal; anda controller controlling an excitation level of the excitation light from at least one of the first and second excitation light sources in accordance with a difference between a level of the light signal received by the first terminal and a level of the light signal received by the second terminal.