Dielectric constant microwave measurement of dielectric medium

Abstract

The invention discloses a dielectric constant microwave measurement of a dielectric medium. The measurement device comprises a mixed ring with a slot-line structure. The mixed ring comprises an input port, an isolation port and two same-phase output ports. Parts of 1 / 4 wavelength of the mixed ring are slot lines. Symmetrical coplanar waveguide transmission lines are adopted in the input port and the same-phase output ports. Multiple array branches are symmetrically loaded on a middle guide band between the same-phase output ports. The array branches are formed by coplanar waveguide transmission lines of open-circuit type terminals. Two signal transmission branches are formed from the input port to the same-phase output ports of the open-circuit type terminals. A plastic pipe used for containing to-be-measured solution is arranged on one of the signal transmission branches on one side. The slot lines are adopted on the isolation port. A Balun which shares the panel with the slot lines is manufactured by use of the etching technology, so balance / unbalance signal conversion is finished. According to the invention, dual-port measurement is achieved, so a problem of multiple solutions can be avoided and the measurement results of the dielectric constants can be quite precise and reliable.

Description

technical field [0001] The invention belongs to the technical field of microwave measuring devices for dielectric constant, and in particular relates to a microwave measuring device for dielectric constant. Background technique [0002] The dielectric constant of matter has always been a fundamental and important issue in the study of the interaction between matter and microwaves. There are many methods used to measure the dielectric constant, which can be mainly divided into resonance method and non-resonance method. Among them, the non-resonant method is relatively simple. Among the non-resonant methods, the transmission-emission method has been widely used in broadband measurements, and even used to measure the dielectric constant of low-loss materials. This measurement method is to load the amplitude and phase information of the scattering parameters of the test device before and after the measured object, and complete the calculation and extraction of the dielectric co...

AI Technical Summary

Problems solved by technology

Especially when the dielectric constants of the two media are very close, the information of the measured scattering parameters will also be very close. The traditional output-reflection method, such as axis measurement, cannot accurately distinguish the information of these small changes, which affects the measurement of the material medium. Judgment of electrical characteristics

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