The Experts below are selected from a list of 4827 Experts worldwide ranked by ideXlab platform
Alexey Shashurin - One of the best experts on this subject based on the ideXlab platform.
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experimental study of atmospheric pressure single pulse nanosecond discharge in Pin to Pin Configuration
Journal of Applied Physics, 2021Co-Authors: Xingxing Wang, Sally P M Bane, Adam Patel, Alexey ShashurinAbstract:We present an experimental study of nanosecond high-voltage discharges in a Pin-to-Pin electrode Configuration at atmospheric conditions operating in a single-pulse mode (no memory effects). Discharge parameters were measured using microwave Rayleigh scattering, laser Rayleigh scattering, optical emission spectroscopy enhanced with a nanosecond probing pulse, and fast photography. Spark and corona discharge regimes were studied for electrode gap sizes of 2–10 mm and a discharge pulse duration of 90 ns. The spark regime was observed for gaps <6 mm using discharge pulse energies of 0.6–1 mJ per mm of the gap length. Higher electron number densities, total electron number per gap length, discharge currents, and gas temperatures were observed for smaller electrode gaps and larger pulse energies, reaching maximal values of about 7.5 × 1015 cm−3, 3.5 × 1011 electrons/mm, 22 A, and 4000 K (at 10 μs after the discharge), respectively, for a 2 mm gap and 1 mJ/mm discharge pulse energy. An initial breakdown was followed by a secondary breakdown occurring about 30–70 ns later and was associated with ignition of a cathode spot and transition to a cathodic arc. A majority of the discharge pulse energy was deposited into the gas before the secondary breakdown (85%–89%). The electron number density after the ns-discharge pulse decayed with a characteristic time scale of 150 ns governed by dissociative recombination and electron attachment to oxygen mechanisms. For the corona regime, substantially lower pulse energies (∼0.1 mJ/mm), peak conduction current (1–2 A), electron numbers (3–5 × 1010 electrons per mm), and gas temperatures (360 K) were observed.
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time resolved measurements of electron density in nanosecond pulsed plasmas using microwave scattering
arXiv: Plasma Physics, 2018Co-Authors: Xingxing Wang, Paul Stockett, Ravichandra Jagannath, Sally P M Bane, Alexey ShashurinAbstract:In this work, Rayleigh microwave scattering was utilized to measure the electron number density produced by nanosecond high voltage breakdown in air between two electrodes in a Pin-to-Pin Configuration (peak voltage 26 kV and pulse duration 55 ns). The peak electron density decreased from 1*10^17 cm^-3 down to 7*10^14 cm^-3 when increasing the gap distance from 2 to 8 mm (total electron number decreased from 2*10^13 down to 5*10^11 respectively). Electron number density decayed on the timescale of about several microseconds due to dissociative recombination.
Juan F Valenzuelavaldes - One of the best experts on this subject based on the ideXlab platform.
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compact and low loss v band waveguide phase shifter based on glide symmetric Pin Configuration
IEEE Access, 2019Co-Authors: Angel Palomarescaballero, Antonio Alexamor, Pablo Padilla, Francisco Luna, Juan F ValenzuelavaldesAbstract:This paper presents a compact and low-loss V-band waveguide phase shifter based on glide-symmetric Pin Configuration. This kind of higher symmetry permits the control and improvement of the electromagnetic behavior or radiofrequency devices, as it is the case of the proposed phase shifter. The study of the dispersion diagram of the phase shifter unitary cell demonstrates that the Pin Configuration is a proper option for introducing a phase shift in a waveguide-based system. There is a significant increase in terms of phase shift when using a glide-symmetric Pin distribution compared to its corresponding non-glide-symmetric Configuration. Through this paper, the key geometrical parameters are also determined. The complete phase shifter is composed of an optimized cascade of tailored unitary cells so that the desired final phase shift value is achieved. A prototype has been manufactured in order to validate the theoretical approach through the comparison of phased shifters with both non-glide-symmetric and glide-symmetric Configurations. The measurement results demonstrate the higher performance and compactness of the glide-symmetric phase shifter. For the same distance, the glide-symmetric version of the phase shifter provides more than 60% of phase shifting compared to the non-glide-symmetric phase shifter. Both phase shifters have a good impedance matching between 46 and 60 GHz and an insertion loss lower than 1 dB, thus clearly enabled as a 5G technology.
Valenzuela Valdes, Juan Francisco - One of the best experts on this subject based on the ideXlab platform.
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Compact and Low-Loss V-Band Waveguide Phase Shifter Based on Glide-Symmetric Pin Configuration
IEEE, 2019Co-Authors: Palomares-caballero Ángel, Alex-amor Antonio, Padilla De La Torre, Pablo, Luna Francisco, Valenzuela Valdes, Juan FranciscoAbstract:This paper presents a compact and low-loss V-band waveguide phase shifter based on glidesymmetric Pin Configuration. This kind of higher symmetry permits the control and improvement of the electromagnetic behavior or radiofrequency devices, as it is the case of the proposed phase shifter. The study of the dispersion diagram of the phase shifter unitary cell demonstrates that the Pin Configuration is a proper option for introducing a phase shift in a waveguide-based system. There is a significant increase in terms of phase shift when using a glide-symmetric Pin distribution compared to its corresponding nonglide- symmetric Configuration. Through this paper, the key geometrical parameters are also determined. The complete phase shifter is composed of an optimized cascade of tailored unitary cells so that the desired final phase shift value is achieved. A prototype has been manufactured in order to validate the theoretical approach through the comparison of phased shifters with both non-glide-symmetric and glide-symmetric Configurations. The measurement results demonstrate the higher performance and compactness of the glidesymmetric phase shifter. For the same distance, the glide-symmetric version of the phase shifter provides more than 60% of phase shifting compared to the non-glide-symmetric phase shifter. Both phase shifters have a good impedance matching between 46 and 60 GHz and an insertion loss lower than 1 dB, thus clearly enabled as a 5G technology.This work was supported in part by the Spanish Research and Development National Program and FEDER under project TIN2016-75097-P, in part by the Universidad de Málaga, under Grant PPIT.UMA.B1.2017/15, in part by the Universidad de Granada under Project PPJI2017.15, and in part by the Universidad de Granada through the grant program ``Becas de iniciación a la investigación'' from the Plan Propio de Investigación
Xingxing Wang - One of the best experts on this subject based on the ideXlab platform.
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experimental study of atmospheric pressure single pulse nanosecond discharge in Pin to Pin Configuration
Journal of Applied Physics, 2021Co-Authors: Xingxing Wang, Sally P M Bane, Adam Patel, Alexey ShashurinAbstract:We present an experimental study of nanosecond high-voltage discharges in a Pin-to-Pin electrode Configuration at atmospheric conditions operating in a single-pulse mode (no memory effects). Discharge parameters were measured using microwave Rayleigh scattering, laser Rayleigh scattering, optical emission spectroscopy enhanced with a nanosecond probing pulse, and fast photography. Spark and corona discharge regimes were studied for electrode gap sizes of 2–10 mm and a discharge pulse duration of 90 ns. The spark regime was observed for gaps <6 mm using discharge pulse energies of 0.6–1 mJ per mm of the gap length. Higher electron number densities, total electron number per gap length, discharge currents, and gas temperatures were observed for smaller electrode gaps and larger pulse energies, reaching maximal values of about 7.5 × 1015 cm−3, 3.5 × 1011 electrons/mm, 22 A, and 4000 K (at 10 μs after the discharge), respectively, for a 2 mm gap and 1 mJ/mm discharge pulse energy. An initial breakdown was followed by a secondary breakdown occurring about 30–70 ns later and was associated with ignition of a cathode spot and transition to a cathodic arc. A majority of the discharge pulse energy was deposited into the gas before the secondary breakdown (85%–89%). The electron number density after the ns-discharge pulse decayed with a characteristic time scale of 150 ns governed by dissociative recombination and electron attachment to oxygen mechanisms. For the corona regime, substantially lower pulse energies (∼0.1 mJ/mm), peak conduction current (1–2 A), electron numbers (3–5 × 1010 electrons per mm), and gas temperatures (360 K) were observed.
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time resolved measurements of electron density in nanosecond pulsed plasmas using microwave scattering
arXiv: Plasma Physics, 2018Co-Authors: Xingxing Wang, Paul Stockett, Ravichandra Jagannath, Sally P M Bane, Alexey ShashurinAbstract:In this work, Rayleigh microwave scattering was utilized to measure the electron number density produced by nanosecond high voltage breakdown in air between two electrodes in a Pin-to-Pin Configuration (peak voltage 26 kV and pulse duration 55 ns). The peak electron density decreased from 1*10^17 cm^-3 down to 7*10^14 cm^-3 when increasing the gap distance from 2 to 8 mm (total electron number decreased from 2*10^13 down to 5*10^11 respectively). Electron number density decayed on the timescale of about several microseconds due to dissociative recombination.
Angel Palomarescaballero - One of the best experts on this subject based on the ideXlab platform.
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compact and low loss v band waveguide phase shifter based on glide symmetric Pin Configuration
IEEE Access, 2019Co-Authors: Angel Palomarescaballero, Antonio Alexamor, Pablo Padilla, Francisco Luna, Juan F ValenzuelavaldesAbstract:This paper presents a compact and low-loss V-band waveguide phase shifter based on glide-symmetric Pin Configuration. This kind of higher symmetry permits the control and improvement of the electromagnetic behavior or radiofrequency devices, as it is the case of the proposed phase shifter. The study of the dispersion diagram of the phase shifter unitary cell demonstrates that the Pin Configuration is a proper option for introducing a phase shift in a waveguide-based system. There is a significant increase in terms of phase shift when using a glide-symmetric Pin distribution compared to its corresponding non-glide-symmetric Configuration. Through this paper, the key geometrical parameters are also determined. The complete phase shifter is composed of an optimized cascade of tailored unitary cells so that the desired final phase shift value is achieved. A prototype has been manufactured in order to validate the theoretical approach through the comparison of phased shifters with both non-glide-symmetric and glide-symmetric Configurations. The measurement results demonstrate the higher performance and compactness of the glide-symmetric phase shifter. For the same distance, the glide-symmetric version of the phase shifter provides more than 60% of phase shifting compared to the non-glide-symmetric phase shifter. Both phase shifters have a good impedance matching between 46 and 60 GHz and an insertion loss lower than 1 dB, thus clearly enabled as a 5G technology.