On the matching medium for microwave-based medical diagnosis
Journal article, 2018

In microwave-based medical diagnosis, reflections of electromagnetic waves from the air-skin interface can be reduced with a proper choice of matching medium such that electromagnetic radiation can be effectively penetrated into and through human bodies. Due to the heterogeneous and lossy nature of tissue and the fact that the electromagnetic problem varies as a function of matching medium, frequency, incident angles and polarization, it is not trivial to analyze the entire propagation phenomena. In this study, transmission of electromagnetic wave through a multi-layer planar human tissue model with different matching medium is considered. The reflected, absorbed and transmitted power components are computed to quantify the transmission performance of the matching medium. Our results show that although reflection can be minimized through a proper choice of matching medium, it does not necessary result in an optimal transmission as the transmitted signal is severely attenuated inside the tissue. Our results also show that the oblique incidence plane wave components, which in general correspond to the non-zero spatial frequency components of a near field distribution, can better penetrate through the tissue when a low-permittivity matching medium is used. These findings suggest that a better signal integrity can be obtained when a low-permittivity matching medium (ϵr between 5 and 30) is used.

matching medium

biomedical imaging

microwave imaging

Author

Hoi-Shun Lui

University of Queensland

Andreas Fhager

Chalmers, Electrical Engineering, Signalbehandling och medicinsk teknik, Biomedical Electromagnetics

Biomedical Physics and Engineering Express

2057-1976 (eISSN)

Vol. 4 3 035015

Subject Categories

Medical Laboratory and Measurements Technologies

Medical Equipment Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1088/2057-1976/aa8a89

More information

Latest update

5/29/2018