Wavelength-division multiplexed optical transmission system

Abstract

A wavelength-division multiplexed optical transmission system to keep the correlation of data patterns among wavelength channels to a low level, assuring a stable transmitting quality. The wavelength-division multiplexed optical transmission system has any of a frame phase changing circuit for mutually differing transmitting frame phases between at least two or more wavelength channels, a scrambling circuit using a data scrambler based on a pseudo random pattern for mutually differing scrambling patterns between two or more wavelength channels, or a dummy data generating circuit for mutually differing invalid data patterns between at least two or more wavelength channels in a wavelength channel group transmitted through the same optical fiber transmitting line when transmitting meaningless data.

1 . A wavelength-division multiplexed optical transmission system for transmitting an optical signal via an optical fiber transmitting line, comprising a dummy data generating circuit for generating mutually differing dummy data patterns between at least two or more wavelength channels among a wavelength channel group which is transmitted through a same optical fiber transmitting line, when said wavelength-division multiplexed optical transmission system transmits dummy data.  
   
   
       2 . A system according to  claim 1 , said dummy data generating circuit further comprising a circuit for using a pattern which is different each other by depending on a transmitter and selected at random as an invalid data pattern.  
   
   
       3 . A system according to  claim 2 , said dummy data generating circuit further comprising a circuit for presetting it to mutually differ dummy data patterns by depending on transmitters.  
   
   
       4 . A system according to  claim 3 , further comprising a controller for monitoring and setting an invalid data pattern of the wavelength channels, wherein said controller has means for setting a dummy data pattern of transmitters so as to mutually differ the invalid data patterns among the wavelength channel group which is transmitted through said same optical fiber transmitting line.