| In spite of its simplicity and versatility, the finite difference time domain (FDTD) technique suffers from serious limitations because of its substantial computer resource it requires to model electromagnetic problems with large computational volumes.; This research work aims at developing a systematic multiresolution time domain (MRTD) scheme from prospective views of both theories and practical applications. A generalized MRTD scheme, on the basis of the cubic spline Battle-Lemarie scaling and high-level resolution wavelet functions has been developed. The MRTD scheme has been applied in conjunction with an adjustable multiple image technique (MIT) for the truncation of a boundary with a perfect electric conductor (PEC) or perfectly magnetic conductor, and an anisotropic perfectly matched layer (APML) for the truncation an open space, including face, edge, and corner APML boundaries. The MRTD formulations retain the content of the leapfrog algorithm as that applied in the conventional FDTD method. Meanwhile, the MRTD scheme, as a generalized Maxwell's solver, has been successfully applied to the analysis of a number of practical electromagnetic applications, such as electromagnetic wave propagation in layered spaces, monolithic millimetre-wave integrated circuits (MMICs), and scattering radar cross sections (RCSs) for different targets. This research has been extensively validated for a variety of applications through comparisons with the available results published in literature.; This research showed that the MRTD scheme is a full wave tool with great potential in solving complicated electromagnetic problems in efficient way, due to its flexibility in modelling complex-shaped geometry, broadband computation with leapfrog time-stepping algorithm; and low sampling rate fitting for large objects. It is can conclude that the MRTD techniques represent a significant generalization of the original FDTD method. It has been shown the MRTD scheme has great advantages over the conventional Yee's FDTD method with respect to computer memory requirements and CPU time for a large amount of practical applications. Undoubtedly, the MRTD will be further investigated and explored and it will be found to have more applications in near future. (Abstract shortened by UMI.)... |
