Permittivity and permeability measurements using stripline resonator cavities-a comparison

Abstract

The permittivity and permeability of five materials were measured during a comparison of the stripline resonator cavity technique. The National Institute of Standards and Technology (NIST) organized this intercomparison in which a total of seven organizations participated. Each participant measured two dielectric materials and three magnetic materials. Results for this comparison suggest that when the stripline resonator is used, dielectric property measurements are not as accurate as magnetic property measurements, provided that a correction for demagnetization is made. The results are compared to 7 mm coaxial transmission line measurements which have an uncertainty of less than 10% for the relative permittivity, 0 r <

Improved Resonator Method for Microwave Testing of Magnetic Composite Sheets

“…However, the variation of Q/Q with tan δ μ , plotted in Fig. 6(b), is found linear, which is also in accordance with the last expression of the proposed formula (11). The numerically calculated relative permeability, μ r A , and loss tangent, tan δ μA , using formula (11) are also found in close agreement with the actual data that are shown in Fig.…”

“…From Fig. 6(a), it is interesting to note that for the lossless case, the variation of fractional change in the resonant frequency with the relative permeability is not linear in nature, which does comply with the proposed formula (11). It is to be noted that, for lossless magnetic samples, change in the quality factor of the TE 104 mode will be nearly zero, i.e., Q ≈ 0 that according to the definition given in (9) makes β ≈ 0.…”

“…The non-resonant techniques usually comprise of the free space method [3]- [6] and the transmission line method [7]- [10]. The resonant technique is most commonly based on the perturbation approach, and is implemented in various forms, e.g., in the planar cavity [11], [12], in 3-D form [13]- [17], and so on. The resonant approach is well known for its simplicity, accuracy, and sensitivity.…”

Broadband Complex Permittivity Measurement of Low Loss Materials Over Large Temperature Ranges by Stripline Resonator Cavity Using Segmentation Calculation Method

“…Then ∆ 1 can be calculated from Equation (17). Equation (15) gives the length of each part at variable temperatures, where l 0m can be calculated through the measured resonant frequency at room temperature.…”

“…This method was first reported by Waldron [10,11] and Maxwell [12,13], improved by Musal [14] and Jones [15,16], and their works were carried out at room temperature. In this paper, we developed the measurement theory by considering the thermal expansion coefficient and the conductivity of the cavity metal as a function of temperature, a test system for measuring the complex permittivity of low-loss dielectrics at high temperatures was build.…”