SURFACE INTEGRAL FORMULATION FOR CALCULATING CONDUCTOR AND DIELECTRICLOSSES OF VARIOUS TRANSMISSION STRUCTURES

The power-loss method, along with a surface integral formulation, has been used to compute the attenuation constant in microstrip and coplan ar structures, This method can be used for the analysis of both open a nd closed structures. Using the surface equivalence principle, the wav eguide walls are replaced by equivalent electric surface currents and dielectric surfaces are replaced by equivalent electric and magnetic s urface currents. Enforcing the appropriate boundary condition, and E-f ield integral equation (EFIE) is developed for these currents. method of moments with pulse expansion and point matching testing procedure i s used to transform the integral equation into a matrix one, The relat ionship between the propagation constant and frequency is found from t he minimum eigenvalue of the moment matrix. The eigenvector pertaining to the minimum eigenvalue gives the unknown electric and magnetic sur face currents.