@article{10902/31897, year = {2023}, month = {11}, url = {https://hdl.handle.net/10902/31897}, abstract = {In this paper, a new iterative method is presented to estimate the dielectric constant and loss tangent for each layer in a Bi-layer dielectric material using an X-band short-circuited rectangular waveguide WR90. The S11-parameter at the reference plane as a function of dielectric constant and loss tangent of each layer is calculated by applying the two-dimensional finite difference in time-domain method (2DFDTD) for the wave equation. Then, the Nelder-Mead algorithm is applied to estimate the dielectric constant and the loss tangent by matching the measured and calculated S11-parameter. This method has been validated on three bi-layer dielectric materials such as Teflon-FR4 Epoxy and FR4 Epoxy-Plexiglas and Plexiglas-Teflon. A comparison of estimated values of the dielectric constant and loss tangent obtained from FDTD-2D Maxwell's equations measurements and 2D-FDTD Wave equation measurements is presented. Remarkably, this method reduces the execution time by a factor of five while maintaining equal precision.}, publisher = {Electrical Engineering Department, University of Nevada}, publisher = {International Journal of Microwave and Optical Technology, 2023, 18(6) 575-582}, title = {New FDTD method to estimate the dielectric constant and loss tangent of a bilayer dielectric material at x-band frequencies}, author = {Ait Benali, Lahcen and Tribak, Abdelwahed and Terhzaz, Jaouad and Fernández Ibáñez, Tomás}, }