Extraction of ε_r(f) and tan δ(f) for printed circuit board insulators up to 30 GHz using the short-pulse propagation technique

Abstract

In this paper, the self-consistent, frequency-dependent dielectric constant ε"r(f) and dielectric loss tan δ(f) of several materials are determined over the range 2 to 30 GHz using a short-pulse propagation technique and an iterative extraction based on a rational function expansion. The simple measurement technique is performed in the time domain on representative printed circuit board wiring. Broadband, fully causal transmission-line models based on these results are generated up to 50 GHz for card wiring using low loss materials including BT, Nelco N4000-13, and Nelco N4000-13SI. Simulation and modeling results highlight the need for the accurate frequency-dependent dielectric loss extraction. Signal propagation based on these results shows very good agreement with measured step and pulse time-do-main excitations and provides validation of the measurement and model generation technique. © 2005 IEEE.