The method and algorithms to extract equivalent initial parameters of coupled lines with losses and dispersion
The extraction problem of the equivalent initial coupled lines (CL) parameters in the form of L, C, R, G matrixes of various types (stripline, coaxial, twisted pairs) is solved. The input data are the measured scattering matrix of CL loaded with the known resistance. Measurements are made at several characteristic excitation modes. A method and algorithms to recover the parameters of CL are developed. The accuracy of determining the initial parameters depends on the scattering matrix measurement errors. Experimental results of extraction initial parameters of twisted pair in a shielding cover are presented. It is shown that initial parameters essentially depend on frequency. Using the obtained initial parameters allows to model RF and microwave devices more precisely including segments of coupled lines with losses and a dispersion.