A simple method to account for edge shape in the conductor loss in microstrip

A technique has been developed to examine the effect of strip edge shape on conductor loss in planar transmission lines using a modified incremental inductance rule. Based on L. Lewin's (1984) and L.A. Vainshteins's and S.M. Zhurav's (1986) zero-thickness strip perturbation in loss calculations, the method requires an expression for the infinitely thin strip inductance as well as prescribed integration stopping points for the different strip shapes. Results comparing losses for different edge shapes in a microstrip system are given, using this method and the Lewin/Vainshtein and Zhurav technique. The differing results of some other published analytical and numerical loss methods based on the surface impedance boundary condition are compared. >