According to the cross phase modulation suppressing device of the present
invention, the wavelength multiplexing optical signal from an optical fiber having
polarization orthogonality between the adjacent channels is split for every channel
and the split optical signals are led to delaying optical waveguides of different
lengths by the AWG (Arrayed Waveguide Grating) connected to a second port of an
optical circulator, and the split optical signals with each delay added are reflected
by the Farraday mirrors in polarization states orthogonal to each other and again
led to the delaying optical waveguides. The reflected lights are combined by the
AWG and supplied to a third port of the optical circulator as the wavelength multiplexing
optical signal with orthogonality of polarization states kept between the adjacent channels.
