The Calibration of the Slotted Section for Precision Microwave Measurements
01 Jan 1954-Review of Scientific Instruments (American Institute of Physics)-Vol. 25, Iss: 1, pp 13-20
TL;DR: In this article, a calibration procedure is presented which compensates rigorously for the effects introduced by discontinuities due to the end of the slot, and due to possible adaptors, coupling elements, bead supports, etc, and the presence of a slot in creating a guide wavelength and characteristic impedance slightly different from that of a guide without a slot.
Abstract: The basic slotted section measurements of VSWR and the location of the voltage minimum are affected by the variety of errors inherent in the slotted section Considered here are those effects, important for precision measurements, introduced by discontinuities due to the end of the slot, and due to possible adaptors, coupling elements, bead supports, etc, and by the presence of the slot in creating a guide wavelength and characteristic impedance slightly different from that of a guide without a slot A calibration procedure is presented which compensates rigorously for these effects in a simple fashion
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TL;DR: In this paper, it is indicated that a low loss, high refractive index, artificial dielectric can be constructed by using powdered conductors if the particles are very small and possess a high electric polarizability.
Abstract: Artificial dielectrics have been constructed with indices of refraction as high as 7.2 at a frequency of 9364 mc/sec by imbedding microscopic conducting flakes in paraffin wax. When good conductors such as Cu and Al are used, the resulting permeability is observed to be complex while the permittivity is substantially real. This phenomenon is in agreement with the theoretical results of Lewin. It is indicated that a low loss, high refractive index, artificial dielectric can be constructed by using powdered conductors if the particles are very small and possess a high electric polarizability.
57 citations
19 citations
TL;DR: The operation and design of the test set and its use as a tool in characterizing transistors, which makes substantial use of automatic control circuitry contributes to an easy and facile interface between machine and operator.
Abstract: A new insertion loss, phase and delay measurement tool has been developed for characterizing gigacycle bandwidth transistors and general two-port networks on a small signal basis over a frequency range from 0.25 to 4.2 gc. Maximum inaccuracies are 0.1 db, 0.6 degree (over a 40-db loss range), and 0.5 nanosecond (over a 20-db loss range). Above 2.0 gc, the errors may double. The particular parameters selected for measurement are closely related to the scattering coefficients of the device under test, evaluated with respect to a 50-ohm impedance level. When measuring transistors, measurement data are corrected for the residuals of jig and bias fixtures. Transformation from the measured parameters to other sets (e.g., h, y, or z matrices) is routine. In order to minimize “instrument zero-line” and eliminate errors from circuit drift, a rapid sampling technique sequentially compares the unknown with a high-frequency reference. Measurement accuracy is held substantially independent of test signal frequency by heterodyning the measurement information to a fixed IF, where detection is performed by “IF substitution”, using adjustable standards of loss, phase, and delay. Substantial use of automatic control circuitry contributes to an easy and facile interface between machine and operator. This paper discusses the operation and design of the test set and its use as a tool in characterizing transistors.
8 citations
TL;DR: The utility of a quarter-wave transformer for precise measurement of complex microwave conductivity of semiconductors has been demonstrated in this paper, where it has been shown that the improvement in measurement accuracy is nearly by a factor of 3 over the conventional reflection measurement using a Teflon transformer.
Abstract: The utility of a quarter-wave transformer for precise measurement of complex microwave conductivity of semiconductors has been demonstrated. It has been shown for a chosen conductivity of 9 /spl Omega//spl dot/cm that the improvement in measurement accuracy is nearly by a factor of 3 over the conventional reflection measurement using a Teflon transformer.
5 citations
01 May 1964
TL;DR: In this article, the authors unterstochten der Temperaturverlauf der DielektrizitAtskonstanten und des Verlustfaktors von linearem and verzweigtem PolyAthylen sowie von Plexiglas untersucht.
Abstract: Bei einer WellenlAnge von 12 mm wurden der Temperaturverlauf der DielektrizitAtskonstanten und des Verlustfaktors von linearem und verzweigtem PolyAthylen sowie von Plexiglas untersucht. Die gefundenen Absorptionsmaxima des PolyAthylens schlie\en sich an die in der Literatur gegebenen Daten an, wAhrend sich bei Plexiglas die Ausbildung eines neuen Maximums anzeigt.
4 citations
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