Extraction of S-Parameters from TDR/TDT Measurements using Rational Functions

This paper discusses the extraction of broad band S-parameter response from transient reflection and transmission measurements. The method discussed uses the Generalized Pencil-of-Function method, recursive deconvolution and time referencing to develop models using rational functions. A low loss printed circuit board plane and a lossy thin film plane have been characterized using this method to extract the two-port S-parameters. These models are SPICE compatible and can be used to simulate the frequency or transient response. The results have been compared with network analyzer measurements to show the accuracy.