A Convenient Method for Measuring Permittivity Using the Slotted Rectangular Waveguide
Yujie Liu, Changying Wan, Guobin Wan, Yingfan Wang, Limin Tu · 2024
This article proposes a convenient method based on the use of a slotted rectangular waveguide (SRW) for determining the complex permittivity of materials under test (MUTs). Because the slots are non-radiating and the electric field between the two slots is the strongest, the MUTs can be put through the slots and partially filled in the SRW for measurements. The line-network-network (LNN) technique is used for the calibration of the test fixtures. An iterative method is used to determine the complex permittivity of the MUT, which partially fills the SRW. During the entire calibration and measurement procedure, the SRW and test fixtures do not need to be disassembled. The calibration standard and MUTs can be placed into the SRW through the slots, and their positions in the SRW can be easily changed. Therefore, this method is convenient and repeatable, especially when there are a large number of MUTs to be measured.