Resonant Frequency of a Rectangular Patch Sensor Covered With Multilayered Dielectric Structures

This paper presents a simple analytical model for the resonant frequency of a rectangular patch sensor covered with multilayered dielectric structures. The accuracy of this model, while the relative permittivity of the dielectric top layers varies from 1 to 10.2, is verified with Ansoft´s high frequency structural simulator (HFSS) calculations and with experimental measurements. Comparison with HFSS simulation results show that the average error of the proposed model for three-layer test structures with various sets of relative permittivities and thicknesses is 2% or smaller. Merits of this model also include low calculation cost and mathematical simplicity. The robustness of this model for test structures with less than three layers is also validated by comparing with experimental measurement, HFSS simulation and well-established theory. This model can also be directly used to predict the resonant frequencies of rectangular patch antennas covered with multilayered dielectric superstrates.