Quasi-Dynamic Green’s Functions for Efficient Full-Wave Integral Formulations for Microstrip Interconnects

Andrea G. Chiariello, Antonio Maffucci

D.I.E.I., University of Cassino and Southern Lazio, Cassino, Italy.
D.I.I., Second University of Naples, Aversa, Italy.

DOI: 10.4236/jemaa.2012.42009                

Abstract

Integral formulations are widely used for full-wave analysis of microstrip interconnects. A weak point of these formulations is the inclusion of the proper planar-layered Green’s Functions (GFs), because of their computational cost. To overcome this problem, usually the GFs are decomposed into a quasi-dynamic term and a dynamic one. Under suitable approximations, the ?rst may be given in closed form, whereas the second is approximated. Starting from a general criterion for this decomposition, in this paper we derive some simple criteria for using the closed-form quasi-dynamic GFs instead of the complete GFs, with reference to the problem of evaluating the full-wave current distribution along microstrips. These criteria are based on simple relations between frequency, line length, dielectric thickness and permittivity. The layered GFs have been embedded into a full-wave transmission line model and the results are ?rst benchmarked with respect to a full-wave numerical 3D tool, then used to assess the proposed criteria.

Keywords

Full-Wave Models; Green’s Function; Integral Formulations; Microstrip Interconnects

Conflicts of Interest

The authors declare no conflicts of interest.

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