A fast and simple quasi-analytic method to simulate mode characteristics in highly overmoded rectangular dielectric waveguide bends is presented. Fast mode-based bend models are necessary, since overmoded rectangular waveguides have become very popular in optical interconnects on printed circuit boards. The proposed method combines a simple mode solver with the formalism that was proposed by Melloni et al. [J. Lightwave Technol.16, 571 (2001)], yielding to a very convenient and accurate quasi-analytic formalism for the bend transfer function based on matrix notation. For that purpose, a simple method to approximate leaky modes is introduced. The model offers the ability to predict individual modal phases and amplitudes within a given bend as well as the calculation of coupling losses and was validated using three-dimensional beam-propagation-method simulation software.
© 2005 Optical Society of America
(000.4430) General : Numerical approximation and analysis
(060.4510) Fiber optics and optical communications : Optical communications
(130.2790) Integrated optics : Guided waves
(130.3120) Integrated optics : Integrated optics devices
(230.7370) Optical devices : Waveguides
Daniel Lenz, Daniel Erni, and Werner Bächtold, "Quasi-analytic formalism for mode characteristics in highly overmoded rectangular dielectric waveguide bends," J. Opt. Soc. Am. A 22, 1968-1975 (2005)