Optical Review

, Volume 12, Issue 6, pp 467–471

A New Method of Solving Multimode Coupled Equations for Analysis of Uniform and Non-Uniform Fiber Bragg Gratings and Its Application to Acoustically Induced Superstructure Modulation


DOI: 10.1007/s10043-005-0467-2

Cite this article as:
Abrishamian, F., Sato, S. & Imai, M. OPT REV (2005) 12: 467. doi:10.1007/s10043-005-0467-2


A new and simple mathematical formulation that is employed to analyze numerically coupled-mode equations modeling uniform and non-uniform gratings in optical fiber is investigated. This method would be straightforward and thus beneficial to solve multimode coupled equations in comparison with a previously used fundamental matrix method, and the Runge--Kutta algorithm. The new formulation proposed in this study is applied to calculate transmission and reflection spectra of core mode and higher-order cladding modes of acoustically induced superstructure modulation caused by microbending through fiber Bragg gratings (FBGs). Co-directional and contra-directional couplings based on acoustically induced modulation in FBGs have been discussed for a variety of induced coupling coefficients.

Key words

fiber Bragg grating (FBG)acoustically induced microbendingcoupled-mode theoryn × n coefficient matrixsimilarity transformation

Copyright information

© The Optical Society of Japan 2005

Authors and Affiliations

  • Fatemeh Abrishamian
    • 1
  • Shinya Sato
    • 1
  • Masaaki Imai
    • 1
  1. 1.Department of Electrical and Electronic EngineeringMuroran Institute of TechnologyMuroran, HokkaidoJapan