Design of highly elliptical core ten-mode fiber for space division multiplexing with 2 × 2 MIMO

Abstract

In this paper, we propose a weakly coupled few-mode fiber requiring only 2 × 2 multi-in multi-out equalizer blocks, which makes it compatible with standard coherent receivers with polarization diversity. The fiber has a highly elliptical core, surrounded by a depressed index trench in the cladding, and supports five spatial modes with twofold polarization degeneracy (ten channels). The fiber is designed to mitigate inter-modal crosstalk since the effective index difference between spatial modes is larger than ∼1 × 10-3 over the C-band. Through numerical simulations, we report on bending loss and other modal characteristics such as effective area and chromatic dispersion. Finally, we briefly discuss the scalability of the design.