Impact of Crosstalk in SDM Short-Reach Systems in Presence of Multicarrier Transmission

The effect of the coherent crosstalk in space-division multiplexed (SDM) optical systems is investigated both with simulations and experimentally. Short-reach links based on direct detection are taken into account with multi-subcarrier modulated signals propagating in few-mode fibers or in multi-core fibers. The limitations induced by the signal beating among the different mode/core channels is evaluated. Countermeasures are proposed, also with suitable experimentation.