Electromagnetic field calculation for a high-frequency wave in a lossy transmission line

The objective of this research is to calculate electromagnetic field distribution on the cross section of a lossy transmission line in a Multi-Chip Module (MCM) for predicting the performance of a high-frequency wave propagation in the module. Our approach is to use the hybrid edge/nodal Vector Finite Element Method (VFEM) and apply the 3-component Measured Equation of Invariance (MEI) boundary condition to the calculation. By using the hybrid edge/nodal VFEM the relation between propagation constant and the field distribution on the cross section of the transmission line is obtained, and by using 3-component MEI boundary the field distribution of an open transmission line is calculated with the limited computer resources. The propagation constant of a lossy transmission line with coated conductor strip is also calculated. This 3-component MEI boundary condition simulates the field propagation on the artificial boundary for the electromagnetic field excited from the surface charge, and from the conductor current density distributions in the axial direction and in the transverse direction. Numerical experiments are performed to test the numerical calculation by comparing calculated transmission loss with the measured data. At high frequency, the calculated results are about 10% lower than the measured data. That's because the ground loss is not included in the calculation.