ELIMINATION OF THE MULTIPLE-SOLUTIONS AMBIGUITY IN PERMITTIVITY EXTRACTION FROM TRANSMISSION-ONLY MEASUREMENTS OF LOSSY MATERIALS

A simple yet powerful method is proposed for removing the multiple solutions problem in the complex permittivity epsilon, determination from measured transmission scattering (S-) parameter measurements of lossy materials. The method uses amplitude-only measurements at two slightly separated frequencies to estimate an accurate initial guess. For this purpose, we derive a one-variable objective function for fast evaluation, which lends itself to measurement automation. The method provides on estimation for real and imaginary parts of the P. which call be utilized as a measure for checking the correctness of initial v estimate. The method is very useful for band-limited measurements. (C) 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 337-341, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24048