REDUCTION OF INTER-MODE CROSSTALK IN OPTICAL SPACE-DIVISION-MULTIPLEXING COMMUNICATION SYSTEMS

An optical SDM system configured to transmit modulated optical signals using a pair of guided modes of a few-mode or multimode fiber such that the two modes of the pair carry light of mutually orthogonal polarizations. Some embodiments are configured for bidirectional signal transport using a different respective pair of guided modes of the fiber for each signal-propagation direction. Some embodiments are configured to use wavelength-division multiplexing in addition to space-division multiplexing. The use of mutually orthogonal polarizations in the disclosed manner can be beneficial, e.g., in that it is capable of significantly reducing the level of inter-mode crosstalk compared to that observed in comparable conventional optical SDM systems.