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Characterization of the dielectric properties of water and methanol in the D-band using a quasi-optical spectroscopy.

ABSTRACT: This work presents the measurement of the permittivities of water and methanol in the D-band. Water is a reference medium for dielectric measurement. The dielectric permittivity of water in the millimeter wave range is a fundamental parameter in many applications, and needs to be investigated systematically. The measurement is conducted using a quasi-optical spectroscopy, which is an improved free-space method more suitable for the millimeter wave range. The theoretical formulae are derived using the signal-flow chart method, which is developed specially for multi-layer operation. This model enables one measure liquid samples. A non-calibration method has been developed to retrieve the permittivity. Water and methanol are measured at several temperatures. The measured results agree with published results in a 4% discrepancy. This work will add new measured data to the permittivities of water and methanol over the whole D-band.

SUBMITTER: Liu X

PROVIDER: S-EPMC6898198 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Characterization of the dielectric properties of water and methanol in the D-band using a quasi-optical spectroscopy.

Liu Xiaoming X Yu Junsheng J

Scientific reports 20191206 1

This work presents the measurement of the permittivities of water and methanol in the D-band. Water is a reference medium for dielectric measurement. The dielectric permittivity of water in the millimeter wave range is a fundamental parameter in many applications, and needs to be investigated systematically. The measurement is conducted using a quasi-optical spectroscopy, which is an improved free-space method more suitable for the millimeter wave range. The theoretical formulae are derived usin ...[more]

PMID: 31811220

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