Open AccessImpact of modulation bandwidth on multiplexing using principal modes in MMF links
Author(s) -
Rohan Prasad,
Kumar Appaiah
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.001779
Subject(s) - multi mode optical fiber , modal dispersion , bandwidth (computing) , modulation (music) , multiplexing , physics , optics , mode coupling , telecommunications , computer science , optical fiber , dispersion shifted fiber , acoustics , fiber optic sensor
Multimode fibers (MMFs) are widely used for short fiber links. However, the data rates through MMFs is limited owing to modal dispersion. The so-called "principal modes" (PMs) permit transmission and multiplexing through the MMFs without modal dispersion for small modulation bandwidths. For larger modulation bandwidths, however, they lose their dispersion-free nature. In this paper, we model the impact of modulation bandwidth and mode coupling strength on the performance of PMs. We develop a simulator that characterizes the dispersion and cross-talk of the PMs of few-mode and large-core graded-index MMFs with mode-dependent losses (MDL). Simulations reveal that for fibers without MDL, for modulation frequencies beyond 10 GHz diminishes the PMs' frequency response by more than 1 dB for 100 m in large-core MMF links and 10 km few-mode fiber links. With MDL, simulations reveal that for modulation bandwidths beyond 2 GHz diminishes the frequency response by 3 dB for a 1 km few-mode fiber and by more than 4 dB for a 1 km large-core multimode fiber. While multiplexing using PMs in large-core MMFs with MDL, we find that for modulation bandwidths beyond 3 GHz, the cross-talk is 20 dB in 1 km large-core MMF links, thereby limiting system performance.