Proposed Raised Cosine FMF for Dispersion Management in Next Generation Optical Networks
Spatial mode division multiplexing (MDM) exploiting the emerging few mode fiber (FMF)
technology is one potential candidate for next generation Petabyte optical communication links. In this
work, we focus on the design issues and specifications of the next generation FMF that will better enable
future MDM networks. These systems suffer from two main optical fiber impairments: intermodal
coupling and dispersion. In this research, we focus on the dispersion management issues through
an FMF optical link. We first define two potential differential mode group delay (DMD) management
strategies, we namely refer as (1) Sawtooth and (2) Triangular. Moreover, we propose and investigate
a novel parametric refractive index profile few mode fiber, referred as raised cosine (RC) function
that has been extensively used in digital communication pulse shaping. We investigate the achievable
DMD for a wide range of the RC shape parameter and identify the design values of 2-mode FMF
fiber. We then improve the RC profile by including additional shaping parameters. This enabled us
to develop one four-mode fiber (4-FMF) and one six-mode fiber (6-FMF) having particularly attractive
dispersion characteristics for three kinds of FMF applications: nz-, p-, and n-DMD.
