Outage Probability Due to Intercore Crosstalk in Dual-Core Fiber Links With Direct-Detection

The outage probability (OP) in short-haul direct-detection (DD) optical links supported by weakly-coupled multicore fiber (MCF) impaired by intercore crosstalk (ICXT) and using ON-OFF keying signaling is assessed theoretically and through simulation. A closed-form expression for the OP is proposed for a single interfering core. This expression is useful to provide fast and reliable performance estimates in preliminary studies of weakly-coupled MCF-based systems where the ICXT is highly correlated along the signal bandwidth, i.e., when the skew-bit rate product is small. Particularly, the results for a 20-km-long link at 10 Gbit/s and walk-off below 1 ps/km are detailed. For high skew-bit rate products, i.e., when the ICXT is decorrelated along the signal bandwidth, the simulation results show that for a typical OP of 10
^-4
, the tolerance to ICXT increases above 4 dB, when compared with low skew-bit rate products. It is also shown that the DD links with finite extinction ratio are more robust to outage induced by the ICXT than those with an ideal extinction ratio.