A novel pseudospectral technique based method of lines for planar circuits

Full-wave electromagnetic modelling of MIC/MMIC is required for efficient and accurate circuit analysis and design. Spectral-domain analysis (SDA) has been utilized frequently in the past but the application is virtually limited to cases where the circuit fits into an orthogonal coordinate system. For the analysis of arbitrarily shaped transmission line discontinuities, finite element/finite difference type methods (FEM/FDM) and transmission line matrix (TLM) method offer a high degree of flexibility. The need for large computer memory and supercomputer power is the main hurdle in implementing these methods. A technique with some potential to overcome these problems is method of lines (MOL). However, discretizing two spatial variables in a circuit that contains fine details requires a large number of lines and again leads to computer-time-intensive algorithms. To eliminate the shortcomings of the conventional MOL and take advantage of the attractive features of SDA, a combination of the two methods, the pseudospectral based method of lines, is developed for the analysis of arbitrarily shaped spatial 3D planar MIC/MMIC. For this application, the pseudospectral based method of lines is numerically very efficient, since most of the unfavorable properties commonly encountered with either SDA or MOL are avoided. The resonant frequency of a microstrip resonator dominant mode is analyzed.