Flanged coaxial microwave probes for measuring thin moisture layers

Author

Li, Liyou L. ; Ismail, Nour H. ; Taylor, Leonard S. ; Davis, Christopher C.

Author_Institution

Dept. of Electr. Eng., Maryland Univ., College Park, MD, USA

Volume

39

Issue

1

fYear

1992

Firstpage

49

Lastpage

57

Abstract

An analytical, closed-form expression is obtained for the input admittance of a flanged, open-ended coaxial line radiating into a layered lossy material. The effect of higher modes as well as the dominant mode have been taken into consideration. The results obtained in the experimental measurement of the microwave reflection coefficient of the probe radiating into very thin water layers are described and compared with the results obtained from numerical calculations based on a theoretical model. The measurements were made in the 5.0-7.0 GHz range. The results demonstrate, for example, the usefulness of this type of device in measuring thin moisture layers in the outer layer of human skin.

Keywords

biomedical measurement; microwave measurement; moisture measurement; probes; skin; 5 to 7 GHz; analytical closed form expression; dominant mode; flanged coaxial microwave probes; flanged open-ended coaxial line; higher modes; human skin outer layer; input admittance; layered lossy material; microwave reflection coefficient; numerical calculations; theoretical model; thin moisture layers measurement; Admittance; Closed-form solution; Coaxial components; Humans; Microwave devices; Microwave measurements; Moisture measurement; Probes; Reflection; Skin; Body Water; Diagnosis, Computer-Assisted; Evaluation Studies as Topic; Humans; Microwaves; Models, Theoretical; Skin;

fLanguage

English

Journal_Title

Biomedical Engineering, IEEE Transactions on

Publisher

ieee

ISSN

0018-9294

Type

jour

DOI

10.1109/10.108127

Filename

108127