부산대학교 도서관

We propose a new measurement method for the simultaneous evaluation of permittivity and permeability of small amount of materials in powder, liquid, or gel form. A plastic toroidal case was used to encapsulate non-solid material under test (MUT), and the whole case was subjected to coaxial line analysis. The volume of MUT required for the case was established as approximately 70 $\mu \text{L}$ , and we removed the plastic parts using high-frequency circuit theory. As a result, constant and nearly ideal relative permittivity and permeability of air were confirmed. Measuring permeability at microwave band of magnetic powder above 45 vol% became possible using the proposed method.