New low-complexity but effective mitigation for penalties from in-band crosstalk of multicore fiber with advanced modulation formats

We have modeled the intercore crosstalk of multicore fiber and proposed an effective method for mitigating the penalties from the crosstalk. Employing the same local oscillator to hybrid with signals in different cores and taking advantage of the estimated phase information of the signal in other cores, the SNR penalty is reduced below 1dB for any core of MCF with QPSK signals before the crosstalk approaches the threshold value where cycle slip occurs, and for 16QAM signal, the crosstalk tolerance has been increased by at most 10dB at 1dB SNR penalty for both inner core and outer core.