A new method of modeling three-dimensional MIC/MMIC circuits: the space-spectral domain approach

A new space-spectral domain analysis is developed to characterize arbitrarily shaped, spatial three-dimensional (3-D) discontinuities in microwave integrated circuits (MICs) and monolithic microwave integrated circuits (MMICs). The method is very general and combines the advantages of the spectral-domain analysis (SDA) with that of the one-dimensional method of lines (MOL). The unique combination of the one-dimensional SDA, using a continuous Fourier transformation, with the one-dimensional MOL, using a discrete Fourier transformation, makes it possible to analyze circuit configurations which were difficult or impossible to analyze before. A comparison of data obtained from the space-spectral domain approach (SSDA) and the SDA and measurements for a rectangular patch resonator shows excellent agreement. The new approach is numerically very efficient and can be applied to planar transmission lines on insulating as well as semiconducting substrates with and without open boundaries. Several resonator structures are analyzed to demonstrate the usefulness of this new method