In a plane perpendicular to the transmission direction, the optical signal field can have two mutually orthogonal and independent vibration directions, generally named X polarization and Y…

In a plane perpendicular to the transmission direction, the optical signal field can have two mutually orthogonal and independent vibration directions, generally named X polarization and Y polarization. Polarization multiplexing utilizes this property of optical signals and modulates service signals in two orthogonal polarization directions of light.