Biological Liquid Monitoring using Microwave Resonator

Abstract

For dielectric characterisation of liquids, a novel microwave sensor is designed on the concept of metamaterial (MTM) by using complementary split ring resonator (CSRR). This work describes an MTM based high-sensitivity microwave sensor with a PDMS channel that can be used for any kind of liquid detection and in a number of biomedical applications. On the ground plane of a dielectric substrate, three CSRRs with squared shapes are engraved. A planar microstrip-line (MTL) carved on the substrate's bottom side generates a time-varying electric field that is connected to the sensor cells to stimulate them. The sensor has been built on a Rogers RT6002 dielectric substrate. The sensitivity of the proposed sensor is demonstrated in laboratory tests with a variety of liquid samples using a Vector Network Analyzer (VNA) setup, where the frequency is different for different dielectric constants. The designed sensor has a remarkable ability to detect minor dielectric variations, in addition to having other beneficial qualities including compact size, easy manufacture, cheap, nonionizing nature, and no risk to human health. The use of the proposed sensor along with additional microwave components for non-invasive disease diagnosis may be encouraged by such crucial properties.