Patent ID: 6678431
Filing Date: 2004-01-13
Classification: G02B,H04B

Abstract:
An apparatus for compensating polarization mode dispersion (PMD) occurring in an optical transmission fiber, the apparatus comprising:a polarization controller (PC) for transforming states and directions of polarization components of an optical signal received from the optical transmission fiber; a polarization rotator for rotating the polarization components of an optical signal output from the PC; a polarization beam splitter (PBS) for separating two orthogonal polarization components of an optical signal output from the polarization rotator, for transmitting a first polarization component to a signal output path and transmitting a second polarization component to a monitoring path; a compensation controller for controlling the PC using an electrical spectrum of an optical signal transmitted to the monitoring path so that the two orthogonal polarization components of an optical input signal to the PBS are aligned to two axes of the PBS; and a rotation controller for controlling the polarization rotator by comparing an optical power of the first polarization component transmitted to the signal output path with an optical power of the second polarization component transmitted to the monitoring path.