Influence of mode coupling on mode group diversity multiplexing in multimode fibers

In this paper, the influence of mode coupling on mode group diversity multiplexing (MGDM) in multimode fibers is investigated. It is found experimentally, that in step index fibers mode coupling is very strong among the lowest mode groups. It is confirmed that mode coupling in graded index fibers is negligible. Theoretical and numerical investigation of the system performance in strong mode coupling conditions, indicates need for greater separation of the lowest MGDM channels.