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A novel method for complex permittivity and permeability measurements of dielectrics has been shown. The method is based on a previously developed transmission-line technique, however, has been modified to allow for dielectric properties estimation with measurements of reflections only. The analysis of measurement errors, resulting from: sample length uncertainty, vector network analyzer uncertainty, and open-end inaccuracy, has been shown in the article. The calibration method using open/short/offset-short standards has been described. The method has been experimentally tested by measurements of three different reference liquid samples. A good agreement between measured values and previously published ones has been obtained. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:727–732, 2014

Miniature rectangular coaxial transmission line (with a 300 × 300 μm outer conductor) is simulated, fabricated, and tested up to the Ka band. It is made by the electrochemical fabrication (EFAB™) of nickel such that the center conductor is supported primarily by ≈λ/4 stubs that also establish a resonant passband. The minimum insertion loss of a 1.67-cm-long test structure is found to be 1.74 dB at the passband center of 29 GHz. This is within 0.57 dB of the lowest insertion loss predicted by full-wave numerical simulations, indicative of the high precision and smooth surface morphology of the EFAB process. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 365–368, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11383

This article introduces a 20-μm tall, 75-μm wide rectangular polyimide core micro coaxial transmission line that can be realized using a simplified fabrication procedure. Measurements of a 4-bend, meandered micro coaxial line demonstrate an 8% increase in the insertion loss and a 2% variation in the phase compared with a straight line of equivalent length. Cross-coupling below 30 dB up to 65 GHz has been measured between two micro coaxial lines separated by 175 μm. These properties make the structures as useful building blocks for highly miniaturized and integrated microwave circuitry. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1291–1293, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25212

In this article, we propose a new method to measure the complex relative permittivity (er = e − je) and permeability (μr = μ − jμ) of liquid- or powder-type materials using a two-port probe which is constructed from coaxial transmission lines. The two-port probe is a simple structure that can be easily fabricated with low cost in comparison with conventional probes which are the type of the cavity and waveguide. And we have adopted the Cole–Cole equation and air-filled coaxial cable for calibrating the proposed probe. To verify the performance of the proposed probe, we measured the properties of materials in the form of liquids and powders and compared the results with those measured by the air-filled coaxial cable, which shows good agreement. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2977–2979, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24793

A new quasianalytical method, the multipole theory (MT) method, is described for the computation of cutoff wavenumbers of TE and TM modes in a rectangular coaxial transmission-line family. An extensive comparison with the exact data of the literature and various configurations of a rectangular transmission-line family shows the accuracy and flexibility of the quasianalytical MT method. It has been shown that the MT method is an effective approach for the analysis of TE and TM modes in a rectangular transmission-line family. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 24: 405–407, 2000.