- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 International Conference on Power Electronics Applications and Technology in Present Energy Scenario (PETPES) - Mangalore, India (2019.8.29-2019.8.31)] 2019 International Conference on Power Electronics Applications and Technology in Present Energy Scenario (PETPES) - Performance Comparison of Root-finding Algorithms for Solar Photovoltaic Emulator
摘要： This paper presents a novel method for tracking the position of a medical instrument’s tip. The system is based on phase locking a high frequency signal transmitted from the medical instrument’s tip to a reference signal. Displacement measurement is established having the loop open, in order to get a low frequency voltage representing the medical instrument’s movement; therefore, positioning is established by means of conventional measuring techniques. The voltage-controlled oscillator stage of the phase-locked loop (PLL), combined to an appropriate antenna, comprises the associated transmitter located inside the medical instrument tip. All the other low frequency PLL components, low noise amplifier and mixer, are located outside the human body, forming the receiver part of the system. The operating details of the proposed system were coded in Verilog-AMS. Simulation results indicate robust medical instrument tracking in 1-D. Experimental evaluation of the proposed position tracking system is also presented. The experiments described in this paper are based on a transmitter moving opposite a stationary receiver performing either constant velocity or uniformly accelerated movement, and also together with two stationary receivers performing constant velocity movement again. This latter setup is implemented in order to demonstrate the prototype’s accuracy for planar (2-D) motion measurements. Error analysis and time-domain analysis are presented for system performance characterization. Furthermore, preliminary experimental assessment using a saline solution container to more closely approximate the human body as a radio frequency wave transmission medium has proved the system’s capability of operating underneath the skin.
关键词： radio frequency (RF),medical instrument,Displacement measurement,phase shift,position tracking
更新于2025-09-19 17:13:59
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Quantum dot light-emitting diodes with an Al-doped ZnO anode
摘要： A study of a hybrid ZnCdSeS/ZnS quantum dot light-emitting diodes (QLEDs) device fabricated with indium tin oxide (ITO)-free transparent electrodes is presented. Al-doped zinc oxide (AZO) prepared by magnetron sputtering is adopted in anode transparent electrodes for green QLEDs with different sputtering pressures. The Kelvin probe force microscopy measurement shows that AZO has a work function of approximately 5.0 eV. The AZO/poly(ethylene-dioxythiophene)/polystyrenesulfonate (PEDOT:PSS) interface can be adjusted by the sputtering pressures, which was confirmed by the hole-only devices. The AZO films with low surface roughness can form a good AZO/PEDOT:PSS interface, which can increase the holes’ injection, and result in improved charge balance. The maximum current efficiency, luminance and external quantum efficiency of the optimized QLEDs devices under a sputtering pressure of 1 mTorr can achieve values of 50.75 cd/A, 102,500 cd/m2 and 12.94%, respectively.
关键词： radio-frequency magnetron sputtering,Al-doped zinc oxide,quantum light-emitting diode,transparent electrode
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Miramar Beach, FL, USA (2019.8.19-2019.8.21)] 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Multispectral Plasmonic Perfect Absorbers Integrated with Room-Temperature VO <sub/>x</sub> Air-Bridge Bolometers
摘要： The roadmap evolution and historical milestones of electromagnetic energy conversion techniques and related breakthroughs over the years are reviewed and presented with particular emphasis on low-density energy-harvest technologies. Electromagnetic sources responsible for the presence of ambient radio-frequency (RF) energy are examined and discussed. The effective use and recycling of such an ambient electromagnetic energy are the most relevant and critical issue for the current and future practicability of wireless energy-harvesting devices and systems. In this paper, a set of performance criteria and development considerations, required to meet the need of applications of ambient electromagnetic energy harvesting, are also derived from the radiating source analysis. The criteria can be calculated from a simple measurement of the I–V nonlinear behavior of RF rectification devices such as diodes and transistors, as well as linear frequency behavior (S-parameters). The existing rectifying devices are then reviewed in light of the defined performance criteria. Finally, a technological outlook of the performances that can be expected from different device technologies is assessed and discussed. Since the proposed spindiode technology would present the most promising device platform in the development of the most useful ambient energy harvesters, a special highlight of this disruptive scheme is provided in the presentation of this work.
关键词： Schottky diode,magnetic tunnel junction (MTJ),energy harvesting,diodes,spindiode,backward diode,metal–insulator–metal (MIM),crystal rectifier,Ambient radio-frequency (RF) energy
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 2nd International Conference on Renewable Energy and Power Engineering (REPE) - Toronto, ON, Canada (2019.11.2-2019.11.4)] 2019 IEEE 2nd International Conference on Renewable Energy and Power Engineering (REPE) - Perovskite solar cells-A futuristic approach
摘要： Simulation data from a ray-tracing tool applied in specific urban environments in the 28-GHz band suggest that the utilization of arbitrary base station (BS) angles in a directional search procedure may not be of maximum benefit for users located in non-line-of-sight positions, because certain angles restrict the radio frequency illumination to a lower maximum power than from others. An appropriate selection of BS angles offers a potential power level benefit of greater than 2 dB in a defined number of consecutive measurements; however, this performance improvement appears to be conditioned by the severity of the existing street canyon propagation and the probability of the angle used. A simple ray tracing method is proposed to approximately identify the most effective BS angles that avoid power emissions in directions largely blocked by nearby buildings. The results indicate that prior site-specific information may be helpful, particularly for systems using analog beamforming.
关键词： Angle of arrival,millimeter wave,user equipment,ray tracing,non-line-of-sight,base station,radio frequency,beam direction
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Rear Heterojunction GaAs Solar Cells With Strain-Balanced GaInAs/GaAsP Quantum Wells
摘要： Simulation data from a ray-tracing tool applied in specific urban environments in the 28-GHz band suggest that the utilization of arbitrary base station (BS) angles in a directional search procedure may not be of maximum benefit for users located in non-line-of-sight positions, because certain angles restrict the radio frequency illumination to a lower maximum power than from others. An appropriate selection of BS angles offers a potential power level benefit of greater than 2 dB in a defined number of consecutive measurements; however, this performance improvement appears to be conditioned by the severity of the existing street canyon propagation and the probability of the angle used. A simple ray tracing method is proposed to approximately identify the most effective BS angles that avoid power emissions in directions largely blocked by nearby buildings. The results indicate that prior site-specific information may be helpful, particularly for systems using analog beamforming.
关键词： Angle of arrival,user equipment,radio frequency,non-line-of-sight,beam direction,base station,millimeter wave,ray tracing
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Understanding CdTe Performance with Engineered Front and Back Interfaces
摘要： Recently, structural health monitoring (SHM) using radio frequency identification (RFID) tag antenna-based sensing (TABS) has received increasing attention because of its wireless, passive, and low-cost characteristics. However, a great challenge in the SHM using RFID TABS is multiple influences in the measurement. This paper presents an ultrahigh frequency RFID sensor system for corrosion detection and characterization. In this paper, a 3-D antenna sensor is designed to work on the surface of a protective coated steel sample. Sweep-frequency measurements are applied for analog identifier with principal component analysis (PCA) to overcome the multiple influences from reader-tag orientation, distance, and environment. Feature extraction and selection though PCA can get robust and sensitive defect information by projecting the test data into an orthogonal feature space. The test results demonstrate that the proposed method can be applied to detect and characterize early-stage corrosion in metals.
关键词： principal component analysis (PCA),radio frequency identification (RFID),structural health monitoring (SHM),Antenna sensor,corrosion detection
更新于2025-09-19 17:13:59
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Single-Mode 940 nm VCSELs With Narrow Divergence Angles and High-Power Performances for Fiber and Free-Space Optical Communications
摘要： This paper presents a novel method for tracking the position of a medical instrument’s tip. The system is based on phase locking a high frequency signal transmitted from the medical instrument’s tip to a reference signal. Displacement measurement is established having the loop open, in order to get a low frequency voltage representing the medical instrument’s movement; therefore, positioning is established by means of conventional measuring techniques. The voltage-controlled oscillator stage of the phase-locked loop (PLL), combined to an appropriate antenna, comprises the associated transmitter located inside the medical instrument tip. All the other low frequency PLL components, low noise amplifier and mixer, are located outside the human body, forming the receiver part of the system. The operating details of the proposed system were coded in Verilog-AMS. Simulation results indicate robust medical instrument tracking in 1-D. Experimental evaluation of the proposed position tracking system is also presented. The experiments described in this paper are based on a transmitter moving opposite a stationary receiver performing either constant velocity or uniformly accelerated movement, and also together with two stationary receivers performing constant velocity movement again. This latter setup is implemented in order to demonstrate the prototype’s accuracy for planar (2-D) motion measurements. Error analysis and time-domain analysis are presented for system performance characterization. Furthermore, preliminary experimental assessment using a saline solution container to more closely approximate the human body as a radio frequency wave transmission medium has proved the system’s capability of operating underneath the skin.
关键词： position tracking,Displacement measurement,phase shift,radio frequency (RF),medical instrument
更新于2025-09-19 17:13:59
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Effect of Ar(3p <sup>5</sup> 4p; 2p)+M → Ar(3p <sup>5</sup> 4s; 1s)+M branching ratio on optically pumped rare gas laser performance
摘要： Optically pumped rare gas laser performance is analyzed as a function of the Ar(3p54p; 2p) + M → Ar(3p54s; 1s) + M branching ratios. Due to the uncertainty in the branching ratios, a sensitivity study is performed to determine the effect on output and absorbed pump laser intensities. The analysis is performed using a radio frequency dielectric barrier discharge as the source of metastable production for a variety of Argon in Helium mixtures over pressures ranging from 200 to 500 Torr. Peak output laser intensities show a factor of 7 increase as the branching ratio is increased from 0.25 to 1.00. The collection of Ar* in Ar(1s4) is inversely proportional to the branching ratio and decreases output laser intensity by reducing the density of species directly involved with lasing.
关键词： Argon,Helium,branching ratio,radio frequency dielectric barrier discharge,metastable production,optically pumped rare gas laser
更新于2025-09-16 10:30:52
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Performance improvement of perovskite solar cells using vanadium oxide interface modification layer
摘要： To improve the performance of perovskite solar cells (PSCs), vanadium oxide (VOx) film was deposited as an interface modification layer (IML) by a radio frequency magnetron sputtering system. The VOx IML was utilized to modify the interface between the indium tin oxide (ITO) anode electrode and the poly(3,4-ethylenedioxythiophene)-poly (styrene sulfonate) (PEDOT:PSS) hole transport layer (HTL). The valence band maximum (VBM) of 4.94 eV of the VOx films was measured by an ultraviolet photoelectron spectroscopy (UPS). Using the optical energy bandgap and the VBM of the VOx film, the conduction band minimum (CBM) energy level was 2.12 eV. This phenomenon verified that the VOx IML could be an electron blocking layer and made a more match energy level between the work function of ITO anode electrode and the highest occupied molecular orbital (HOMO) of PEDOT:PSS HTL. Using the measurement of contact angle, the surface energy of PEDOT:PSS HTL spun on VOx IML and ITO anode electrode was evaluated as 47.76 mJ/m2 and 38.21 mJ/m2, respectively. The enhanced surface energy of the PEDOT:PSS HTL spun on VOx IML could improve the adhesion ability of the perovskite absorption layer spun on the PEDOT:PSS HTL. Consequently, the carrier extraction could be enhanced and the leakage current could be reduced by the predominant functions of VOx IML. Therefore, the performances of the PSCs were significantly improved. The power conversion efficiency (PCE) of the PSCs with VOx IML was enhanced from 9.43% to 13.69% in comparison with the conventional PSCs without VOx IML.
关键词： Vanadium oxide,Perovskite solar cells,Interface modification layer,Radio frequency magnetron sputtering system
更新于2025-09-16 10:30:52
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Revealing charge-tunneling processes between a quantum dot and a superconducting island through gate sensing
摘要： We report direct detection of charge tunneling between a quantum dot and a superconducting island through radio-frequency gate sensing. We are able to resolve spin-dependent quasiparticle tunneling as well as two-particle tunneling involving Cooper pairs. The quantum dot can act as an RF-only sensor to characterize the superconductor addition spectrum, enabling us to access subgap states without transport. Our results provide guidance for future dispersive parity measurements of Majorana modes, which can be realized by detecting the parity-dependent tunneling between dots and islands.
关键词： radio-frequency gate sensing,charge tunneling,Majorana modes,superconducting island,quantum dot
更新于2025-09-16 10:30:52