Study and Simulation of a Biosensor Based on a SRR

摘要

In this study, a microwave bio-electromagnetic sensor for biomedical applications is developed. The operating principle of these sensors is based on the interaction of the electromagnetic near-field generated by the sensors with the samples under investigation without labeling or chemical reaction. The proposed biosensor consists of a double planar split-ring resonator (SRR. The main advantages obtained by using metamaterials are a reduction in the structure size and an increase in sensor sensitivity. The SRR can be considered as an RLC resonator circuit. At resonance, SRR develops an intense and localized electric field confined in the gap region, enabling sensitive detection of extremely small amounts of simples in a small area. In order to achieve a high sensitivity and increasing the high electric field region, a new split gap are adding in each rings. The detection method is based on the principle of the resonant frequency shift which caused by the changes in capacitive and inductive effects, due to the presence of samples mainly in the SRR split/split. The shift of the resonance frequency in the presence of a sample material is explained by using An analytical equivalent circuit model which describes the sensor and the sample material as a layered system of homogeneous media. Results obtained from these model are compared with the results of full-wave numerical simulation (HFSS) based on the finite element method (FEM). Results of numerical HFSS simulations, and equivalent circuit model computations are shown to be in good agreement.