| 摘要 |
PURPOSE:To continue the transmission and reception of light via another nondefective system although a system at the reception side has a fault, by mixing optical signals of plural systems to transmit them at the transmission side and distributing these optical signals at the reception side. CONSTITUTION:The electric signals fed to a transmitter 1 are converted individually into optical signals by transmission converters 3 and 4, respectively. These optical signals are mixed by an optical mixer 15 via MODEMs 5 and 6 and transmitted to an optical cable 16. The optical signals led to a receiver 2 are distributed to systems A and B by an optical distributor 15 and then to reception converters 12 and 13 via MODEMs 10 and 11 to be converted into electric signals. Therefore the light can be normally transmitted although the optical signal energy is reduced down to half compared with a normal state and even if either one of converters 3 and 4 has a fault. |
