An Analytical Gradient Model for the Characterization of Conductor Surface Roughness Effects

A novel analytical gradient model (AGM) is presented to characterize the conductor surface roughness of microstrip lines. Based on the AGM, both the electrical and thermal performance of microstrip line with rough surface are investigated in detail. The numerical results show that the AGM gives more accurate prediction than the conventional Hammerstad model. In addition, the AGM is convenient for guiding the design of microwave devices.