Study on the difference of high frequency dielectric properties of biological tissues measured by air and packed coaxial probe.
10.7507/1001-5515.202303066
- Author:
Yangchun QIN
1
;
Lin YANG
2
;
Feng FU
1
;
Meng DAI
1
;
Liang ZHANG
3
Author Information
1. Department of Military Biomedical Engineering, Air Force Medical University, Xi'an 710032, P. R. China.
2. Department of Aerospace Medicine, Air Force Medical University, Xi'an 710032, P. R. China.
3. Basic Medical Science Academy, Air Force Medical University, Xi'an 710032, P. R. China.
- Publication Type:Journal Article
- Keywords:
Biological tissue;
Dielectric properties;
Equivalent circuit model;
High frequency;
Open-ended coaxial probe
- MeSH:
Reproducibility of Results;
Sodium Chloride;
Calibration
- From:
Journal of Biomedical Engineering
2023;40(5):886-893
- CountryChina
- Language:Chinese
-
Abstract:
In this paper, the differences between air probe and filled probe for measuring high-frequency dielectric properties of biological tissues are investigated based on the equivalent circuit model to provide a reference for the methodology of high-frequency measurement of biological tissue dielectric properties. Two types of probes were used to measure different concentrations of NaCl solution in the frequency band of 100 MHz-2 GHz. The results showed that the accuracy and reliability of the calculated results of the air probe were lower than that of the filled probe, especially the dielectric coefficient of the measured material, and the higher the concentration of NaCl solution, the higher the error. By laminating the probe terminal, liquid intrusion could be prevented, to a certain extent, to improve the accuracy of measurement. However, as the frequency decreased, the influence of the film on the measurement increased and the measurement accuracy decreased. The results of the study show that the air probe, despite its simple dimensional design and easy calibration, differs from the conventional equivalent circuit model in actual measurements, and the model needs to be re-corrected for actual use. The filled probe matches the equivalent circuit model better, and therefore has better measurement accuracy and reliability.
