DISTORTION COMPENSATION CIRCUIT FOR BROAD BAND OPTICAL FIBER COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a distortion compensation circuit that is used for a broadband optical fiber communication system. SOLUTION: The distortion compensation circuit compensates composite second order CSO/composite third beat CTB distortion of a transmission signal caused by harmonics intermodulation by nonlinear elements in the system. A distortion compensation circuit 110 includes a split means such as a directive coupler that divides an inputs signal into a 1st signal and a 2nd signal. The 1st signal is sent to a 1st path and the 2nd signal is sent to a 2nd path. A CSO/CTB generator 140 connects to the 2nd path to receive the 2nd signal and selectively generates a compensation CSO/CTB output from the 2nd signal. Furthermore, a coupling means such as another directive coupler 130 is placed to a termination section of the 1st path and the 2nd path to couple a compensation CSO/CTB output of the CSO/CTB with the 1st signal. The compensation CSO/CTB output is used to cancel the CSO/CTB distortion generated in the optical fiber communication system.