Low Complexity Kernel-MSER based Equalizer for Crosstalk Mitigation in Multicore Fiber Communication

Multicore Fiber based backhaul network is essential to support huge data for future wireless applications. Performance of multi-core fiber (MCF) communication systems is severely affected by inter-core crosstalk (IC-XT), which limits its application for long-reach backhaul optical network. The nonlinear IC-XT interference in MCF makes the overall system nonlinear, thereby resulting in a poor bit error rate (BER) performance. Conventional Volterra series based nonlinear equalizers have high computational complexity, and are impaired by modeling error due to the truncation of polynomial kernel. Recently, reproducing kernel Hilbert space (RKHS) based kernel least mean square (KLMS) equalizer has been proposed in the literature for mitigating IC-XT interference in MCF communication systems. However, KLMS based equalizer is based on minimum mean square error (MMSE) criterion which considers only second order statistics of error. In this paper, multivariate kernel minimum symbol error rate (KMSER) adaptive nonlinear equalizer in RKHS is proposed for mitigating IC-XT impairments in MCF communication systems. Simulations show that the proposed KMSER equalizer exhibits superior BER performance and less computational complexity over the existing Volterra series equalizer, and KLMS equalizer.