Novel algorithms for the characterization of n-port networks by using a two-port network analyzer

• Main Authors: B. Will, I. Rolfes, B. Schiek
• Format: Article
• Language: deu
• Published: Copernicus Publications 2007-06-01
• Series: Advances in Radio Science
• Online Access: http://www.adv-radio-sci.net/5/13/2007/ars-5-13-2007.pdf

The measurement of the scattering matrices of n-port networks is an important task. For this purpose two ports of the n-port network are connected with the network analyzer and the remaining ports are connected to reflecting terminations. In order to specify the scattering matrix of a n-port network with the multi-port method (Rolfes et al., 2005), <i>n</i> reflecting terminations are required from which at least one reflection factor needs to be known. <br><br> There are some cases, in which the multi-port method shows weak convergence properties. For example, a T-junction cannot be identified if the reflecting terminations used are short circuits and if the line length is equivalent to a multiple of a half wavelength. This is due to the fact that the two ports connected to the network analyzer become isolated. <br><br> Two new algorithms, named the sub-determinant method and the wave-identification method, respectively, which employ a second set of reflection terminations that have to differ from the first set, allow to identify every n-port network without the necessity to distinguish different cases. Both methods are based on least square algorithms and allow to determine all scattering parameters of a n-port-network directly and uniquely.