In the article, a new method for the estimation of electric permittivity of threads (filaments) was presented. The proposed recursive method is based on the results of computer simulation of 3D model of transmission stripline. This model contains a model of flat fabric having threads, with which electric permittivity should be determined. The described procedure uses the method proposed by Barry to obtain permittivity of flat fabric from the so-called s parameters of the simulated stripline. In the proposed method, the permittivity of the flat fabric obtained from simulation is compared with the measured value of permittivity of real flat fabric in order to estimate the threads’ permittivity. This comparison is needed to obtain the electric permittivity of threads forming this fabric. The article also presents examples of the obtained values of threads’ permittivity and discussion about the accuracy of the method. The presented method will be useful in situations where the knowledge of permittivity of threads is necessary in the conducted research.
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