Mitigating the Inter-Core Crosstalk of Multicore Fiber Transmission by Orthogonal Filtering

We for the first time proposed to utilize the orthogonal filtering technique to suppress the inter-core crosstalk (IC-XT) in multicore fiber (MCF) transmission. It could simplify the implementation of weakly-coupled MCF (WC-MCF) signal reception without multiple-input and multiple-output (MIMO) digital signal processing, by extracting the individual lanes separately. Effective IC-XT mitigation using a pair of orthogonal filters are demonstrated for MIMO-free 2-core MCF transmitted signal receptions. 600-Gbps 64-QAM (quadrature amplitude modulation) signal transmission over 100-km MCF is emulated by constructing a concrete transmission model based on coupled nonlinear Schrodinger equations. Maximum Q factor improvement of 6 dB can be achieved using orthogonal matching filters to suppress IC-XT at −10dB. The effect of spatial mode dispersion on the filter orthogonality performance is also analyzed.