Available online at www.sciencedirect.com ScienceDirect Materials Today: Proceedings 18 (2019) 1796–1802 www.materialstoday.com/proceedings 2214-7853© 2019 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of INTERNATIONAL CONGRESS ON SEMICONDUCTOR MATERIALS AND DEVICES. ICSMD-2017 Usage of T-Resonator Method at Determination of Dielectric Constant of Fabric Materials for Wearable Antenna Designs Özen Bayraktar, Dilek Uzer, S. Sinan Gültekin and Rabia Top * Department of Electrical and Electronics Engineering, Selcuk University, Konya, 42075, Turkey. *Department of Electrical and Electronics Engineering, Karamanoglu Mehmetbey University, Karaman, 70100, Turkey. Abstract In this study, determination of dielectric constants of fabric materials accurately by using T resonator method is aimed. Dielectric constant is one of the most important parameters that have a large effect on micro strip antenna performance. Small shifting at dielectric constant can cause huge alterations on electrical parameters of the antenna, especially at high frequencies. For this reason, a T resonator is designed on the wool felt fabric as the lower layer material at constant frequencies and the resonator dimensions are calculated. Using these calculated values, the finite element method is simulated with a High Frequency Electromagnetic Field Simulation (HFSS) as a resonator. After some size optimizations, the dielectric constant of the fabric was obtained correctly from the simulations. In order to validate the accuracy of the study and the values obtained, T resonator design on woolen felt material is manufactured and measurements of the resonator is realized with a vector network analyzer. Measurements of this resonator are compared with results from simulations and calculations. As a result, it has been shown that the dielectric constant of any fabric can be accurately determined using an easy, fast and inexpensive method and can be used in wearable micro strip antenna designs © 2019 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of INTERNATIONAL CONGRESS ON SEMICONDUCTOR MATERIALS AND DEVICES. Keywords:T resonator; dielectric measurement; HFSS; fabric materials; woolen felt * Corresponding author. Tel.: +90.332.223 20 42. E-mail address: rabiacaliskantop@gmail.com