| Popis: |
When measuring dielectric properties of heterogeneous layered media such as biological tissues in vivo, the probe sensing depth is a crucial parameter. We studied the effect of the coaxial probe diameter and working frequency on its permittivity sensing depth, using computational modeling and simulation of the probes and of the layered non-biological and biological media. Our results suggest that larger probes and higher frequency increase the permittivity sensing depth. For all models, the measured permittivity was dominated by the surface layer only. These results suggest the limitations of such probes for in vivo biomedical diagnostic applications, in terms of detecting dielectric contrasts in the tissues below the skin. |
