Circular polarization division multiplexing for faster coherent fiber optic communication systems

Quadrature Phase Shift Keying along with Polarization Division Multiplexing is used in 100G Fiber Optic Transceivers for maximizing the fiber spectral efficiency. PDM in these systems involve multiplexing of linearly polarized optical signals. In the present article, we extend this concept of polarization multiplexing to circularly polarized signals. Here, for the first time, we propose the use of circularly polarized beams in addition to linearly polarized ones and QPSK for enhancing bit rate of transceivers without affecting the spectral width of the transmitter.