Analysis of Planar Structures for Applications in Sensing Systems
Planar Sensor, CSRR, CIDC, Bio-inspired Antenna, Soil water content, Permittivity measurements.
Two sensors for the characterization of the dielectric constant of different types of materials have been implemented and one of them applied in the determination of the soil water content (θ), while the other is a bio inspired antenna based on the Shiso leaf. The proposed sensors consist of in: The shape of the antenna patch is inspired by the Shiso leaf, whose scientific name is Perilla Frutescens. A complementary interdigital capacitor (CIDC) is inserted into the geometry; A microstrip antenna with a circular patch in a container printed on ABS filament, based on the complementary split-ring resonator (CSRR) structure. The operating principle is based on the displacement of the element’s resonance frequencies when the relative permittivity of the material under test (MUT) is changed. Several simulations were performed, with the data obtained, two empirical models are proposed. To validate its effectiveness, measurements were made with dielectric substrates that have the dielectric constant known in the literature. The second sensor can be applied to different types of materials, in this work it was used to determine the percentage of water contained in different types of soils. The prototypes were built and the results obtained in the measurements were compared with the results of other studies, thus validating the effectiveness of the proposed sensors.