| 摘要 |
PROBLEM TO BE SOLVED: To enable inter-polarized-wave level ratio monitoring and inter-polarized-wave level ratio control capable of monitoring inter-polarized waves affected by a PDL(Polarization Dependent Loss).SOLUTION: A transmission system of a polarized multiplex optical transmission system for transmitting two optical signals of the same wavelength by multiplexing them with polarized waves orthogonal to each other comprises: a tone signal generator for generating two tone modulation signals of different frequencies; and two optical modulators for superimposing different tone modulation signals on the two optical signals, respectively. A relay system or an optical node comprises: a tone modulation signal extracting part for extracting two tone modulation signal components from inputted polarized multiplex optical signals; and an inter-polarized-wave level ratio detecting part for determining inter-polarized-wave level ratio from the two tone modulation signal components. Thereby, the inter-polarized-wave level ratio is monitored and PDL compensation is performed. |
