An optical emission unit includes a signal arrangement unit that generates respective pairs of phase-conjugate signals of a plurality of systems on the basis of externally input signals of a plurality of systems, mixes together the pairs of phase-conjugate signals, and then arranges the pairs of phase-conjugate signals discretely in orthogonally polarized electric fields, and an optical modulation unit that converts electric signals from the signal arrangement unit into optical signals and outputs the optical signals to the optical transmission unit, and the optical reception unit includes a photoelectric conversion unit that converts the optical signals transmitted by the optical transmission unit into electric signals, and a signal reconstruction unit that reconstructs the original signals of the plurality of systems by synthesizing the intermixed and discretely arranged signals from the photoelectric conversion unit.