| This thesis presents two numerical methods for analyzing transient electromagnetic behavior in stationary objects. The first is a finite element method for eddy current analysis that employs convolution in the time domain. The second method is geared toward the solution of pulse propagation in lossless monolithic microwave integrated circuits and is a generalized version of the finite difference time domain algorithm.; Heretofore, transient eddy currents have usually been solved by using low order finite difference methods. The standard finite element method is inefficient due to the non-self-adjoint time derivative {dollar}{lcub}partialoverpartial t{rcub}{dollar}. However, in this thesis, this operator is converted to symmetric form through the application of convolution and results in a new class of efficient high order finite element methods.; Existing algorithms for the solution of wave propagation in the time domain are, in general, restricted to a regular grid. Because of this limitation, millions of unknowns are required to model both scattering and microstrip problems accurately. In order to overcome this deficiency, the finite difference time domain algorithm is generalized in this thesis to non-regular grids. The approach taken is to exploit the complementary nature of Delaunay tetrahedral and Voronoi polyhedral meshes.; To demonstrate the usefulness of these methods, a number of example problems are solved. To validate the eddy current analysis, a series of three test problems of increasing complexity are solved, leading to the analysis of a two-dimensional thin film recording head. To validate the wave propagation analysis, three three-dimensional example problems are solved including an open-ended microstrip antenna. The power of the time domain solution is demonstrated by calculating the frequency domain reflection coefficients from the time domain data. |
