Modeling of modal dispersion in multimode and multicore optical fibers

Modal dispersion in strongly-coupled multimode and multicore optical fibers can be viewed as a generalization of polarization-mode dispersion in single-mode fibers. Due to the similarities between these two transmission effects, the conventional Jones and Stokes calculus for polarization-mode dispersion can be extended to the case of modal dispersion. In this paper, we review and expand the theoretical framework used for the representation of modal dispersion in Stokes space by the modal dispersion vector. We show, for the first time, that the modal dispersion vector can be written as a weighted sum of the Stokes vectors representing the principal modes with the corresponding mode group delays as coefficients. This constitutes a fundamental relationship that leads to a reinterpretation of the modal dispersion vector and can be used to derive its properties.