Capteurs inductifs radiofréquences pour la caractérisation diélectrique de tissus biologiques

Radiofrequencies inductive sensors allow non contact characterization of biological tissues to be carried out, by the estimate of the intrinsic dielectric properties of tissues such as the conductivity (σ) and the permittivity (ε). As these properties are related to the physiological or pathological state of the tissue, they can be used as relevant indicators. The paper focuses on a measurement method dedicated to the estimation of these parameters. The proposed method is based on the use of radiating RF surface resonators, used as transmitter and receiver when coupled with a distant probe. Placed at the surface of the media to be evaluated, this type of resonator is sensitive to the modifications of the induced magnetic field, which are sensed through the impedance changes of the resonator. The sensitivity to the dielectric parameters of such sensors are evaluated on tissue phantoms made of saline agarose gels.