The metrology of electrical impedance at high frequency: a review

Abstract

The measurement of electrical impedance in the high-frequency range (loosely speaking, from 100 kHz to 100 MHz) is a common characterization technique in research and applications concerning condensed matter physics, engineering and biology. Commercial instruments for impedance measurement have specifications, including frequency range and base accuracy, continuously improving. The calibration of impedance instruments and standards in the high-frequency range represents a tough challenge for metrology laboratories; measurement methods and traceability paths are not as firmly established as those employed for lower (audio) or higher (microwave) frequencies. In the last few years, the problem has received increased attention from the metrology community. The paper gives a review of recent results in the field.

Early detection and monitoring of plant diseases by Bioelectric Impedance Spectroscopy

“…Bioelectrical impedance measurements have been widely used in the past 50 decades, giving rise to a great number of techniques and methods able to characterize solids, liquids and suspensions, and, lately, to biological tissues and fluids, either in vitro or in vivo [1], some of which having clinical applications [2]. Electric Impedance Spectroscopy, EIS, is an incoming technique that has been extensively used to characterize electrical properties of plant tissue [3], especially in what concerns to fruits and their respective quality [3] [5] [6], maturation process [4], and influence of temperature or other external agents [7], and to specific botanical tissues changes under controlled factors [8] [9] [10].…”

“…Nowadays, instruments having high accuracy, high resolution and frequency ranges extending from a few Hz to tens of MHz are commercially available [1]. Despites that, these solutions are quite expensive or, on the other hand, lack a true frequency bandwidth analysis, which is mandatory for the EIS technique.…”

“…Despites that, these solutions are quite expensive or, on the other hand, lack a true frequency bandwidth analysis, which is mandatory for the EIS technique. In addition, these equipments are unspecified for biological applications, which could give rise to several misunderstanding about the impedance measurements and consequently lead to false results [1].…”

Broadband Reflectometry for Diagnostics and Monitoring Applications

“…FDR can rely on a well-established calibration procedure, such as the SOL calibration [32]. The error model can be identified using a signal flow graph, and the SOL-calibrated reflection scattering parameter can be calculated from measurements of , , and , which are the reflection scattering parameters when an open, short, and matched loads, respectively, are connected.…”

Capacitance Spectroscopy of Thin‐Film Solar Cells

“…Measurements at higher frequencies, above about 1 MHz, require extra attention to circuit components, connections, and calibration [10].…”