Abstract: Various examples related to microwave dielectric analyzers and their use are provided. In one example, a microwave dielectric analyzer includes a measurement apparatus having a conductive electrode that can couple to a microwave analyzer and processing circuitry that can determine a dielectric characteristic of the dielectric specimen using a reflection coefficient measured by the microwave analyzer. The dielectric characteristic can be determined using a computational electromagnetic model of the measurement apparatus. The reflection coefficient can be measured by the microwave analyzer with the dielectric specimen in contact with the conductive electrode and/or sandwiched between conductive electrodes. The conductive electrodes can be axially aligned, and the second electrode may not be coupled to the microwave analyzer.

Abstract: Various examples related to microwave dielectric analyzers and their use are provided. In one example, a microwave dielectric analyzer includes a measurement apparatus having a conductive electrode that can couple to a microwave analyzer and processing circuitry that can determine a dielectric characteristic of the dielectric specimen using a reflection coefficient measured by the microwave analyzer. The dielectric characteristic can be determined using a computational electromagnetic model of the measurement apparatus. The reflection coefficient can be measured by the microwave analyzer with the dielectric specimen in contact with the conductive electrode and/or sandwiched between conductive electrodes. The conductive electrodes can be axially aligned, and the second electrode may not be coupled to the microwave analyzer.

Abstract: Various examples of methods and systems are disclosed for correction of phase and amplitude errors that occur in transmission lines connecting transmitter/receiver devices to measurement fixtures. In one example, a method is described that includes using time domain processing to determine a phase shift from the measurement fixture that can occur between calibration measurements and measurements of the specimen under test. In another example, a method is described that includes frequency-domain processing of the signals to obtain both phase and amplitude corrections. Including these phase and amplitude corrections in the calibration procedure can reduce or minimize the errors induced in the measurements when the transmission line(s) experience either temperature changes or physical deflections, among other things.

Abstract: Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.

Abstract: Various examples of methods and systems are disclosed for correction of phase and amplitude errors that occur in transmission lines connecting transmitter/receiver devices to measurement fixtures. In one example, a method is described that includes using time domain processing to determine a phase shift from the measurement fixture that can occur between calibration measurements and measurements of the specimen under test. In another example, a method is described that includes frequency-domain processing of the signals to obtain both phase and amplitude corrections. Including these phase and amplitude corrections in the calibration procedure can reduce or minimize the errors induced in the measurements when the transmission line(s) experience either temperature changes or physical deflections, among other things.

Abstract: Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.

Abstract: Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.

Abstract: Various examples related to microwave dielectric analyzers and their use are provided. In one example, a microwave dielectric analyzer includes a measurement apparatus having a conductive electrode that can couple to a microwave analyzer and processing circuitry that can determine a dielectric characteristic of the dielectric specimen using a reflection coefficient measured by the microwave analyzer. The dielectric characteristic can be determined using a computational electromagnetic model of the measurement apparatus. The reflection coefficient can be measured by the microwave analyzer with the dielectric specimen in contact with the conductive electrode and/or sandwiched between conductive electrodes. The conductive electrodes can be axially aligned, and the second electrode may not be coupled to the microwave analyzer.

Abstract: Various examples of methods and systems are disclosed for non-contact determination of coating thickness. In one example, among others, a method includes illuminating a surface having a layer of a coating material with electromagnetic (EM) energy transmitted at two or more frequencies, obtaining measured reflection data from reflected EM energy, and matching the measured reflection data to modeled reflection data of a reflection model based upon minimization of an error between the measured reflection data and the modeled reflection data to determine a measured thickness of the layer. In another example, a system includes a probe configured to illuminate an area of the surface including a layer of a coating material with EM energy and receive reflected EM energy, and a processing device configured to determine a measured thickness of the layer based upon minimization of an error between measured reflection data and modeled reflection data.

Abstract: Various examples are provided for fragmented aperture antennas. In one example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements, where positioning of the conducting elements in adjacent rows are offset based upon a fixed skew angle. In another example, a fragmented aperture antenna includes a two-dimensional lattice comprising a combination of first and second geometric conducting elements, where a second geometric conducting element provides a connection between adjacent sides of diagonally adjacent first geometric conducting elements. In another example, a fragmented aperture antenna includes a two-dimensional lattice of conducting elements having a single common non-rectangular shape, where the conducting elements interleave in a digitated fashion. Diagonally adjacent conducting elements overlap along a portion of adjacent edges of the diagonally adjacent conducting elements.

Abstract: Various examples of methods and systems are disclosed for correction of phase and amplitude errors that occur in transmission lines connecting transmitter/receiver devices to measurement fixtures. In one example, a method is described that includes using time domain processing to determine a phase shift from the measurement fixture that can occur between calibration measurements and measurements of the specimen under test. In another example, a method is described that includes frequency-domain processing of the signals to obtain both phase and amplitude corrections. Including these phase and amplitude corrections in the calibration procedure can reduce or minimize the errors induced in the measurements when the transmission line(s) experience either temperature changes or physical deflections, among other things.

Abstract: Various examples of methods and systems are disclosed for non-contact determination of coating thickness. In one example, among others, a method includes illuminating a surface having a layer of a coating material with electromagnetic (EM) energy transmitted at two or more frequencies, obtaining measured reflection data from reflected EM energy, and matching the measured reflection data to modeled reflection data of a reflection model based upon minimization of an error between the measured reflection data and the modeled reflection data to determine a measured thickness of the layer. In another example, a system includes a probe configured to illuminate an area of the surface including a layer of a coating material with EM energy and receive reflected EM energy, and a processing device configured to determine a measured thickness of the layer based upon minimization of an error between measured reflection data and modeled reflection data.