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Accurate measurement circuit and high-frequency sensors with sufficient bandwidth are necessary for the analysis of individual partial discharge (PD) pulses. In this paper, a testbed is designed and constructed for the investigation of DC PD pulses. The testbed is equipped with a 50 ohm transmission line (TL) that terminate to an oscilloscope for measuring the charge displacement current generated by PD pulses. Besides the oscilloscope measurements, two types of electromagnetic field sensors (D-dot and B-dot) were developed to capture the EM fields of the PD pulses propagating through the TL. The main goal of this paper is to investigate the DC PD pulses through the EM fields and the corresponding discharge current pulses that are considered as calibrating signals for the developed D-dot and B-dot sensors. The results of DC cavity discharge measured by the constructed testbed and the EM field sensors demonstrate close agreement with the reference PD pulses measured via oscilloscope.

This study aims to classify and compare AC and DC partial discharge (PD) based on PD pulse waveform analysis. To achieve this goal, we designed a testbed that enables precise measurements of individual PD pulses. The testbed is used for collecting data from four different types of PDs including cavity, surface, corona, and floating potential discharges generated by individual PD source samples. All samples were examined under AC, positive DC, and negative DC electrical stresses, through which we captured thousands of PD pulses. We classify the waveforms of each PD type into representative groups associated to their discharge mechanisms. The statistical data of the measured pulses are utilized to identify the differences between AC and DC PDs while the clustered patterns of PD amplitude versus their temporal characteristics serve as a means to classify the types of PDs under AC and DC electrical stresses.

The impacts of wall–target interaction on matched illumination waveforms for through-the-wall radar imaging are examined via finite-difference time-domain simulation. Returns from various wall–target scenarios are considered as a function of the target-to-wall separation in order to examine the effectiveness of the so-called primary-wave target response in the matched illumination implementation. The primary-wave target response is shown to effectively maximize the signal-to-interference-and-noise ratio (SINR) in through-wall radar applications where the wall–target interaction is minor, and the primary-wave response closely resembles the full-wave target response, which contains all wall–target interactions. The ability of the primary-wave target response to maximize the SINR can be degraded by relatively minor errors in the wall–target transfer function caused by the incomplete wall–target physics inherent to the scheme. In such cases, the resulting matched illumination waveform spectrum is generally characterized by narrowband energy concentrated at suboptimal frequencies.

Reports on the IEEE Special Interest Group on Humanitarian Technology (SIGHT) program, a network of volunteers from around the globe that teams with underserved communities and local organizations to leverage technology for sustainable development.

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A fast method for determining the fields scattered from a perfect electric conductor (PEC) strip or PEC semicircular cylinder loaded with semicircular dielectric cylinders illuminated by a TE/TM plane wave or an electric/magnetic line source is presented. The method is based on expanding the field on the circle containing the scatterer in terms of a Neumann series, which satisfies the continuity of the tangential electric field. The continuity of the tangential magnetic field is satisfied by using the orthogonality of Gegenbauer polynomials. Some numerical results are presented to demonstrate the efficacy of the proposed solution.

The IEEE's Student Professional Awareness Experience (SPAx) program is aimed at developing key nontechnical skills that are crucial for success in the workplace but are not taught in the classroom. Engineering is broader than the various technical skills covered in the typical engineering curriculum. Nontechnical competencies are just as critical to engineers as their technical training. The student professional awareness activities of the SPAx program are oriented to enhance the leadership, career, and professional development skills of engineering students.

All three spectral sums in the cylindrical harmonic eigenfunction expansion of the Lorentz gauge-free space magnetic vector potential dyadic Green's function are closed. The specific techniques used to close the radial, azimuthal, and axial spectral sums are detailed. The magnetic vector potential dyadic Green's function spectral closure process is paralleled with that of the corresponding scalar Green's function eigenfunction expansion. Fundamental relationships between the scalar and dyadic spectral closures are noted. The cancellation of static and traveling wave pole contributions is noted in order to achieve reduced expressions at each stage of the spectral closure process. The techniques used here to close the spectral sums in the free space eigenfunction expansion are also applicable to certain scattering geometries when the method of scattering superposition is employed. Thus, the complexity of the dyadic Green's function computation may be reduced.