Estimation of attenuation of EM waves propagating through interface biological tissue/free space

Biological medium surrounding an implanted device is characterized by a high dielectric permittivity and a loss factor. This fact results in a degradation of the electromagnetic signal. It's important to note that biological tissue and free space have a high dielectric constant which leads to a strong wave reflection from the interface. The phenomenon of the total internal reflection at the interface between the biological tissue and the air is under consideration. The improving the transmission coefficient between an implanted antenna and an antenna of reader can be obtained by using additional matching layer. The influence of this layer on the wave propagation on the interface of biological tissue/free space was studied analytically and by using full wave simulation. Realization of a miniature dipole antenna with SAW resonator was suggested for wireless remote temperature monitoring. The proposed results were confirmed by the full-wave simulation using SEMCAD X by SPEAG and the experimental validation.