Design of Weakly-Coupled 16-Vector-Mode Coaxial Bragg FMF for Short-Haul Communication

Utilizing weakly-coupled few-mode-fibers (FMFs) for MIMO-DSP eliminating in short-haul mode division multiplexing(MDM) systems has attracted much attention recently, as an effective solution to suppress modal crosstalk. In this article, we propose a weakly-coupled 16-vector-mode coaxial Bragg FMF supporting 16 vector modes(HE 11a , HE 11b , TM 01 , HE 21a , HE 21b , TE 01 , HE 31a , HE 31b , EH 11a , EH 11b , HE 12a , HE 12b , EH 21a , EH 21b , HE 41a , HE _{\mathrm {41b}} ) which works across the C-band and explore the possibility for weakly-coupled Bragg FMFs. We optimize the geometric parameters and evaluate their effects on modal n_{eff} , min \Delta n_{eff} , and A_{eff} . The DMD, modal confinement loss and bending loss are also investigated. The simulation results indicate that the proposed fiber can obtain large min \Delta n_{eff} between adjacent vector modes ( \sim 2\times 0.0001 ), and can be a promising candidate for MIMO-DSP simplified short-haul MDM transmission systems.