Permittivity Measurement of Biological Materials with Improved Microwave Cavity Perturbation Technique

The resonant cavity perturbation technique is usually used to measure the complex permittivity of various dielectric materials at microwave frequency. The real and imaginary part of the complex permittivity of the material under test can be extracted from the measured resonant frequency shift and the change of quality factor (Q factor) of the resonance cavity with inserted samples. In this paper, an improved resonance cavity perturbation technique is employed to measure the complex permittivity of biological materials, including porcine fat, marrow and liver etc. The measured results agree well with the known data, demonstrating the potential validity of our method. This method can hopefully be extended to permittivity measurement of other biological materials, even the tissues of human body.