Patent ID: 7505881

Claim:
A method for modeling one or more electromagnetic field modes of a waveguide, the method comprising: sampling a two-dimensional cross-section of the waveguide; and using a computer to perform the steps comprising: calculating a first matrix using the sampled two-dimensional cross-section of the waveguide, the first matrix comprising a plurality of elements and having a first bandwidth, the plurality of elements of the first matrix representing an action of Maxwell's equations on a transverse magnetic field within the waveguide; rearranging the plurality of elements of the first matrix to form a second matrix having a second bandwidth smaller than the first bandwidth; shifting the second matrix and inverting the shifted second matrix to form a third matrix; calculating one or more eigenvalues or eigenvectors of the third matrix corresponding to one or more modes of the waveguide; and calculating one or more mode propagation losses corresponding to the one or more modes of the waveguide.