Extended spatial domain and hybrid time-domain analyses for microwave circuits

The development of integration technology for microwave circuits is based on accurate and efficient full-wave analysis and design tools. A full-wave spatial domain analysis is developed to analyze arbitrarily shaped planar microwave circuits. By introducing a lumped element incorporation scheme, the spatial domain analysis is extended to analyze the microwave circuits having lumped elements such as Wilkinson power dividers. In addition, the proposed matched load and excitation scheme replaces the conventional voltage gap source excitation method in the spatial domain analysis. Three-dimensional general structures can be analyzed more efficiently using the finite difference time-domain method. Bondwire interconnect and microstrip-to-waveguide transition structures are studied using the finite difference time-domain method. Finally, a hybrid time-domain analysis using the finite difference and finite element time-domain methods is proposed to analyze three-dimensional locally detailed and curved structures. The validity of this hybrid method is demonstrated using waveguide iris problems and via hole grounded microstrips.