Numerical analysis of microstrip structures using the complex images method

This thesis presents an efficient full wave numerical analysis method for three dimensional microstrip structures inside a stratified media. The method can analyze both vertical and horizontal components of the currents. The conducting structures are modeled using a mixed potential integral equation (MPIE). The boundary conditions on the interfaces between dielectric layers are satisfied through the use of appropriate dyadic Green's functions in the spectral domain. Numerical evaluation of Sommerfeld integrals that are encountered during the transformation of the Green's function to the spatial domain is avoided using the complex images method (CIM). A modified CIM is proposed for efficient solution of vertical conductors currents. The modification maintains the rigorous nature of the full-wave analysis method while achieving the same numerical efficiency for both vertical and horizontal components of currents. The frequency sweep is made more efficient by interpolating the coefficients of the complex images used to represent the Green's functions in the spatial domain.; The CIM is combined with the MPIE and the method of moments (MoM) to produce a versatile numerical analysis tool for printed geometries in multilayered media. The numerical accuracy and convergence of the tool is established via an analytical benchmark. The accuracy of the method is also tested against commercially available full-wave analysis packages. Good agreement is obtained for a wide class of stacked microstrip antennas and circuits. The resulting analysis tool is applied successfully to the numerical analysis of microstrip antennas, and for a variety of feeding techniques. The tool is also applied to the analysis of microwave circuits, and passive MMIC components in the presence of finite ground planes, slots in the ground plane and to a wide frequency band interconnects. The tool is used to accurately predict the radiated emissions levels from printed interconnect structures. An efficient radiation susceptibility prediction procedure is suggested based on the analysis tool. In combination with time domain convolution, the tool is used to analyze interconnect systems with active circuits in the time domain. This approach does not compromise the accuracy of the analysis of the active circuit nor the interconnect system.