- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Tunable Phase Shifter Based on Few-Layer Graphene Flakes
摘要： This letter presents a voltage-controlled tunable phase shifter based on few-layer graphene. The phase shifter consists of a stub-loaded line, composed of a microstrip line with a stub attached to it through a taper and graphene pad. The bias voltage applied to the graphene pad determines a variation of graphene resistance, which eventually causes the phase change. Without any voltage bias, graphene exhibits high resistance, thus isolating the stub and leading to a low phase shift. As the bias voltage is increased, graphene resistance is lowered, the effect of the stub is more pronounced, and the phase shift is increased. A prototype operating in the frequency range from 5 to 6 GHz has been designed and tested. The measured maximum phase shift obtained is 40°, and the corresponding degradation of the insertion loss is 3 dB.
关键词： tunable microwave devices,graphene,phase shifter,Few-layer graphene
更新于2025-09-23 15:22:29
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Defected Ground Structure for Characteristic Enhancement of CSRR-based Substrate Integrated Waveguide BPF
摘要： Defected ground structure (DGS) is frequently involved to improve the characteristic response of microwave devices. In this paper, investigation of DGS utilization for characteristic enhancement of substrate integrated waveguide (SIW) bandpass filter (BPF) composed of complimentary-split-ring-resonator (CSRR) is presented. The filter is deployed on an FR4 epoxy dielectric substrate with the thickness of 1.6 mm and the dimension of 45 mm × 40 mm. The BPF which is designed by two reversely arranged CSRR incorporated on the SIW conductor surface provides passband extension at higher frequency producing the bandwidth response around 9 GHz. However, the use of CSRR also provides some unsatisfactory response at high frequency region requiring for the enhancement. By involving DGS into the BPF, the characteristic response at high frequency region could be enhanced with the bandwidth response achieves up to 10% improved.
关键词： microwave devices,Defected ground structure (DGS),bandpass filter (BPF),complimentary-split-ring-resonator (CSRR),substrate integrated waveguide (SIW)
更新于2025-09-23 15:21:01
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Breathing dynamics in a gain-guided dissipative soliton- similariton fiber laser
摘要： In this paper, the energy recovery in microstrip passive circuits from the power losses into heat is studied. For this purpose, a thermoelectric generator (TEG) based on the Seebeck effect principle is used, which converts part of the power dissipated into heat to dc electrical power. A solution integrating the TEG with the microstrip circuit is proposed, and design guidelines in order to optimize the recovered power keeping a good isolation between the RF signal and the TEG system are provided. As will be shown, under moderate applied signal powers of just 1–5 W, the levels of recovered power in microstrip passive circuits can be notable. As a demonstrator circuit, an integration device formed by an embedded microstrip bandpass filter for WiMAX applications and a TEG is designed, fabricated, and characterized (thermal and electrically). Different scenarios are considered, depending on frequency and thermal loads. For an applied in-band CW input signal power of 2 W at 3.48 GHz, a recovered power of around 250 μW has been continuously supplied to the electrical load. Several aspects, such as efficiency and future improvements, are also discussed.
关键词： power applications,Average power handling capability (APHC),microwave devices,planar circuits,energy recovery,electro-thermal analysis,energy harvesting
更新于2025-09-23 15:19:57
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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) - Measured dc Arc-flash Risk in a Photovoltaic System
摘要： In this paper, the energy recovery in microstrip passive circuits from the power losses into heat is studied. For this purpose, a thermoelectric generator (TEG) based on the Seebeck effect principle is used, which converts part of the power dissipated into heat to dc electrical power. A solution integrating the TEG with the microstrip circuit is proposed, and design guidelines in order to optimize the recovered power keeping a good isolation between the RF signal and the TEG system are provided. As will be shown, under moderate applied signal powers of just 1–5 W, the levels of recovered power in microstrip passive circuits can be notable. As a demonstrator circuit, an integration device formed by an embedded microstrip bandpass filter for WiMAX applications and a TEG is designed, fabricated, and characterized (thermal and electrically). Different scenarios are considered, depending on frequency and thermal loads. For an applied in-band CW input signal power of 2 W at 3.48 GHz, a recovered power of around 250 μW has been continuously supplied to the electrical load. Several aspects, such as efficiency and future improvements, are also discussed.
关键词： power applications,Average power handling capability (APHC),microwave devices,planar circuits,energy recovery,electro-thermal analysis,energy harvesting
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 7th Workshop on Advances in Information, Electronic and Electrical Engineering (AIEEE) - Liepaja, Latvia (2019.11.15-2019.11.16)] 2019 IEEE 7th IEEE Workshop on Advances in Information, Electronic and Electrical Engineering (AIEEE) - Phase and Attenuation Characteristics of Models of GaAs Semiconductor Waveguides in Case of Two Layers
摘要： Models of cylindrical multilayer semiconductor-anisotropic-semiconductor dielectric-anisotropic-semiconductor waveguides are presented in this paper. We have selected n-GaAs semiconductor and TM-15 dielectric as a core of the presented waveguides. Anisotropic TM-15 and Rb1?x(ND4)D2PO4 dielectrics and n-InAs1-xSbx semiconductor we used for the external layers of waveguides. The influence of different core materials and temperature to the waves phase characteristics and attenuation was evaluated. Differential Maxwell’s equations, coupled mode, and boundary condition methods were used during the investigation. The density of electrons was constant and equal to N = 5·1019 m–3 during all investigations. The temperature has varied in the range of 125–200 K. Results have showed that material of the core, external layers and temperature has a big impact on the phase and attenuation characteristics of the waveguide and these types of waveguides could be used in the manufacture of phase shifters and attenuators.
关键词： phase characteristics,microwave devices,attenuation,semiconductor waveguides
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) - AlGaAs/InGaP MBE-grown heterostructures for 1.73eV Solar Cells With 18.7% Efficiency
摘要： In this paper, the energy recovery in microstrip passive circuits from the power losses into heat is studied. For this purpose, a thermoelectric generator (TEG) based on the Seebeck effect principle is used, which converts part of the power dissipated into heat to dc electrical power. A solution integrating the TEG with the microstrip circuit is proposed, and design guidelines in order to optimize the recovered power keeping a good isolation between the RF signal and the TEG system are provided. As will be shown, under moderate applied signal powers of just 1–5 W, the levels of recovered power in microstrip passive circuits can be notable. As a demonstrator circuit, an integration device formed by an embedded microstrip bandpass filter for WiMAX applications and a TEG is designed, fabricated, and characterized (thermal and electrically). Different scenarios are considered, depending on frequency and thermal loads. For an applied in-band CW input signal power of 2 W at 3.48 GHz, a recovered power of around 250 μW has been continuously supplied to the electrical load. Several aspects, such as efficiency and future improvements, are also discussed.
关键词： power applications,Average power handling capability (APHC),microwave devices,planar circuits,energy recovery,electro-thermal analysis,energy harvesting
更新于2025-09-16 10:30:52
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Programmable Hybrid Circuit Based on Reconfigurable SPP and Spatial Waveguide Modes
摘要： A programmable hybrid circuit is proposed, which is composed of two reconfigurable spoof surface plasmon polariton (SPP) waveguides loaded with varactor diodes and a substrate integrated waveguide (SIW). By manipulating their dispersion behaviors, the band-pass effect is achieved in the hybrid circuit, in which the upper and lower cutoff frequencies are determined by the SPP waveguide and SIW, respectively. When two SPP waveguides are configured to have the same cutoff frequency that is higher than the SIW’s cutoff, the proposed circuit can realize a power division; when one SPP waveguide is reconfigured to reject the waves from SIW, this circuit will be a band-pass filter. As a typical application, a logic “OR” gate with 2-bit coding is designed by programming the bias voltages applied to the varactor diodes loaded on the unit structures of the SPP waveguides. All functions are demonstrated by measurement results that agree with numerical simulations very well. The work provides more potential applications in multifunctional integrated circuits and digital communication systems.
关键词： substrate integrated waveguide,microwave devices,spoof surface plasmon polaritons,programmable controls
更新于2025-09-11 14:15:04
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[IEEE 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz2018) - Nagoya, Japan (2018.9.9-2018.9.14)] 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Perspective Field Emitters For Electron-Beam Microwave Devices Of Short-Wave Millimeter And Submillimeter Range
摘要： In this report, distributed field emitters are considered, which are perspective for use in miniature but high-voltage electronic devices operating in a technical vacuum. The main attention is paid to the latest developments of the authors on the creation of a new type cathodes: multitip silicon cathodes with protective metal-fullerene coating and multilayer cathodes prepared from the brought into contact materials with different work function. The possibility of obtaining with the help of these cathodes field emission currents and current densities sufficient for maintenance of operation of microwave devices of millimeter and submillimeter range is demonstrated.
关键词： millimeter and submillimeter range,microwave devices,multilayer cathodes,metal-fullerene coating,field emitters,multitip silicon cathodes
更新于2025-09-09 09:28:46