Evaluation of a VNA-based material characterization kit at frequencies from 0.75 THz to 1.1 THz

Khalid, A. , Cumming, D. , Clarke, R., Li, C. and Ridler, N. (2016) Evaluation of a VNA-based material characterization kit at frequencies from 0.75 THz to 1.1 THz. In: 2016 IEEE 9th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies (UCMMT), Qingdao, China, 05-07 Sep 2016, pp. 31-34. ISBN 9781509022779 (doi: 10.1109/UCMMT.2016.7873952)

Abstract

This paper describes an initial assessment of a commercially available THz material characterization kit (MCK). The assessment is based on the measurement of several material samples. The MCK comprises two conical waveguide horn transitions and two sections of low-loss corrugated waveguide. A gap between the two corrugated waveguides allows the material samples to be inserted into the system during measurement. The MCK is attached to a THz Vector Network Analyzer (VNA), which measures S-parameters, in the frequency domain, of a material under test (MUT). A computer-based algorithm employing an iterative calculation derives values for material parameters (e.g. permittivity) from the measured S-parameters of the MUT. A MCK has been evaluated over the frequency range 0.75 THz to 1.1 THz, to assess the plausibility of results that can be obtained using such a technique. Two VNAs utilizing frequency extender heads were used for the investigation, with measurements being made with reference to a range of different calibration techniques and different calibration standards. Whilst some of the results obtained look reasonable, a significant proportion of the results were either difficult to interpret or showed inexplicable (i.e. non-physical) behavior. This indicates that much work is still needed before this technique can be used routinely for the measurement of material parameters at these very high frequencies.

• Item Type: Conference Proceedings
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Li, Professor Chong and Cumming, Professor David and Khalid, Dr Ata-Ul-Habib
• Authors: Khalid, A., Cumming, D., Clarke, R., Li, C., and Ridler, N.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• ISBN: 9781509022779
• Copyright Holders: Copyright © 2016 IEEE
• First Published: First published in 2016 IEEE 9th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies (UCMMT): 31-34
• Publisher Policy: Reproduced in accordance with the publisher copyright policy