- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2018 IEEE 3rd International Conference on Integrated Circuits and Microsystems (ICICM) - Shanghai, China (2018.11.24-2018.11.26)] 2018 IEEE 3rd International Conference on Integrated Circuits and Microsystems (ICICM) - A Novel LC VCO with High Output Power and Low Phase Noise Using Differential Active Inductor
摘要： This paper presents a novel LC voltage-controlled-oscillator (VCO) based on active inductor (AI). Taking advantage of equivalent RLC model of the AI, a novel tunable differential AI (DAI) is designed and used to act as the LC tank of the VCO. First, a tunable DAI with cascode-structure and current-mirror feedback networks is designed to achieve high quality factor (Q) and high equivalent parallel resistance (Rp). Then, the DAI is used to replace LC in VCO to realize good comprehensive performance of VCO such as low phase noise, low power consumption and high output power. Based on TSMC 0.18μm RF CMOS process, the novel VCO is verified by Agilent’s Advanced Design System (ADS). The results show that under the supply voltage of 1.8V, the output power reaches up to -4.2 dBm, a frequency tuning range is in 1.126-2.713 GHz, and the phase noise at 1-MHz offset is -117.2 dBc/Hz. A power of only 13.6 mW is consumed.
关键词： power consumption,output power,phase noise,LC voltage-controlled-oscillator,active inductor
更新于2025-09-23 15:22:29
-
Improvement of the Beam-Wave Interaction Efficiency Based on the Coupling-Slot Configuration in an Extended Interaction Oscillator
摘要： A method aimed at improving the beam-wave interaction efficiency by changing the coupling slot configuration has been proposed in the study of extended interaction oscillators (EIOs). The dispersion characteristics, coupling coefficient and interaction impedance of the high-frequency structure based on different types of coupling slots have been investigated. Four types of coupled cavity structures with different layouts of the coupling slots have been compared to improve the beam-wave interaction efficiency, so as to analyze the beam-wave interaction and practical applications. In order to determine the improvement of the coupling slot to a coupled cavity circuit in an EIO, we designed four nine-gap EIOs based on the coupled cavity structure with different coupling slot configurations. With different operating frequencies and voltages takes into consideration, beam voltages from 27 to 33 kV have been simulated to achieve the best beam-wave interaction efficiency so that the EIOs are able to work in the 2π mode. The influence of the Rb and the ds on the output power is also taken into consideration. The Rb is the radius of the electron beam, and the ds is the width of the coupling slot. The simulation results indicate that a single-slot-type EIO has the best beam-wave interaction efficiency. Its maximum output power is 2.8 kW and the efficiency is 18% when the operating voltage is 31 kV and electric current is 0.5 A. The output powers of these four EIOs that were designed for comparison are not less than 1.7 kW. The improved coupling-slot configurations enables the extended interaction oscillator to meet the different engineering requirements better.
关键词： Output power,Coupling slot configuration,Extended interaction oscillator,Beam-wave interaction efficiency
更新于2025-09-23 15:22:29
-
[IEEE 2020 17th International Bhurban Conference on Applied Sciences and Technology (IBCAST) - Islamabad, Pakistan (2020.1.14-2020.1.18)] 2020 17th International Bhurban Conference on Applied Sciences and Technology (IBCAST) - Comprehension of overhanging structure distortion via selective laser melting based on theory of constraining force induced distortion
摘要： The aim of this paper is to present results on output power level distributions of radio base stations (RBSs) and user devices connected to a wideband code division multiple access-based third generation (3G) mobile communication network in India and relate the results to realistic human exposure to radio frequency (RF) electromagnetic ?eld (EMF) emitted by the corresponding RBSs and the devices. The output power level distributions have been obtained through network-based measurements. In downlink, data from 868 RBSs were gathered during seven days. The RBSs were connected to ?ve different radio network controllers (RNCs) located in different regions of India. The mean, the median, and the 95th percentile RBS output power values were found to be 24%, 21%, and 53%, respectively, of the maximum available power. In the uplink direction, output power levels of 3G devices connected to 1256 RBSs and the same ?ve RNCs as in the downlink were assessed separately for voice, data, voice + data, and video applications. In total, more than 1 million hours of data traf?c and more than 700 000 h of voice calls were measured in the uplink. The mean output power for the voice, data, the voice + data, and the video were found to be around 1%, 3%, 2%, and 4%, respectively, of the maximum available power for the 3G user devices. The ?ndings are in line with previously published results obtained in other networks in Europe, and demonstrate that knowledge on realistic power levels is important for accurate assessments of the RF EMF exposure.
关键词： UMTS,Output power,realistic exposure,WCDMA,power distributions
更新于2025-09-23 15:21:01
-
Improved Leakage and Output Characteristics of Pixelated LED Array for Headlight application
摘要： We investigated the effects of etching conditions on the performance of light-emitting diodes (LEDs) of various sizes aimed at vehicle headlamp applications. Photoluminescence (PL) images showed that after wet etching, the percentage of bad LED arrays significantly increased from 75% to 94%, and the leakage current at ?5 V significantly increased from 1.14 × 10?9 A to 5.02 × 10?6 A. It was shown that plasma etching turned an Ag layer into Ag particles, the size and density of which depended on the treatment time and Ag layer thickness. These Ag particles served as micro-masks during dry etching. Plasma etching produced relatively uniform hillocks of diameters 0.9–1.43 μm and heights 0.85–2.5 μm. Moreover, the PL images showed that dry etching did not degrade the LED arrays. Furthermore, the light output power of the dry-etched LEDs was higher than that of the wet-etched LEDs. For example, the output power levels of the dry-etched LEDs (chip sizes: 240 × 290 μm2, 240 × 490 μm2, and 490 × 1190 μm2) at 100 mA were 20.4%, 15.0%, and 11.2% higher than those of the corresponding wet-etched LEDs, respectively. Moreover, we demonstrated a vehicle headlamp unit consisting of Ag-particle-based plasma-etched LEDs.
关键词： leakage current,vehicle headlamp,light output power,etching,LED
更新于2025-09-23 15:21:01
-
[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Wide-Band Gunn Diodes Based on Graded-Gap InGaP/ InP As
摘要： The paper presents the results of numerical experiments on the oscillation generation using the n+-n-n+ transfer electron device based on InGaP/InPAs graded-gap semiconductor compounds at different Ga and As distributions. The active region of the diode is 2.5 μm with an ionized impurity concentration of 1016 cm–3. It is paper shown that the output power and the efficiency of Gunn generators increase several times when the InGaP/InPAs graded-gap semiconductors are used. The reasons for this increase are considered. The highest power of 11.3 kW/cm2 with efficiency of 10.2% at frequency of 40 GHz belong to In0.4Ga0.6P/InP0.4As0.6 diode.
关键词： graded-gap semiconductor,indium gallium phosphide,intervalley electron transfer,indium phosphide with arsenide,Gunn diode,transfer electron device,output power
更新于2025-09-23 15:21:01
-
[IEEE 2019 19th International Workshop on Junction Technology (IWJT) - Kyoto, Japan (2019.6.6-2019.6.7)] 2019 19th International Workshop on Junction Technology (IWJT) - Comparing RTA and Laser SPE & LPE Annealing of Ge-epi with Si, Sn & C Implantation for Well Mobility/Strain Engineering
摘要： The aim of this paper is to present results on output power level distributions of radio base stations (RBSs) and user devices connected to a wideband code division multiple access-based third generation (3G) mobile communication network in India and relate the results to realistic human exposure to radio frequency (RF) electromagnetic ?eld (EMF) emitted by the corresponding RBSs and the devices. The output power level distributions have been obtained through network-based measurements. In downlink, data from 868 RBSs were gathered during seven days. The RBSs were connected to ?ve different radio network controllers (RNCs) located in different regions of India. The mean, the median, and the 95th percentile RBS output power values were found to be 24%, 21%, and 53%, respectively, of the maximum available power. In the uplink direction, output power levels of 3G devices connected to 1256 RBSs and the same ?ve RNCs as in the downlink were assessed separately for voice, data, voice + data, and video applications. In total, more than 1 million hours of data traf?c and more than 700 000 h of voice calls were measured in the uplink. The mean output power for the voice, data, the voice + data, and the video were found to be around 1%, 3%, 2%, and 4%, respectively, of the maximum available power for the 3G user devices. The ?ndings are in line with previously published results obtained in other networks in Europe, and demonstrate that knowledge on realistic power levels is important for accurate assessments of the RF EMF exposure.
关键词： UMTS,power distributions,Output power,realistic exposure,WCDMA
更新于2025-09-23 15:19:57
-
A novel hybrid system consisting of a dye-sensitized solar cell and an absorption refrigerator for power and cooling cogeneration
摘要： To improve the energy conversion e?ciency of a dye-sensitized solar cell (DSSC), a novel hybrid system representatively consisting of a DSSC and an absorption refrigerator (APR) is put forward, in which the APR is used to thermally harness the part of high wavelength sunlight that not converted by the DSSC. The amount of heat from the DSSC is calculated, and mathematical formula for energy conversion e?ciencies and output powers of the DSSC, APR and hybrid system are derived. Numerical calculations show that the maximum output power density and maximum energy conversion e?ciency of hybrid system are enhanced by 9.93% and 9.92% in comparison with that of the single DSSC, respectively. Integration of APR to DSSC is a feasible route to effectively improve the energy conversion e?ciency. Comprehensive sensitivity analyses are conducted to explore how the whole hybrid system performance depends on various working conditions and designing parameters, including porous nano-TiO 2 ?lm thickness, photoelectron absorption coe?cient, internal irreversibility factor, heat transfer coe?cient and various temperatures. The research results can provide some new understandings for further enhancing the DSSC performance.
关键词： Parametric study,Dye-sensitized solar cell,E?ciency,Absorption refrigerator,Hybrid system,Output power density
更新于2025-09-23 15:19:57
-
Polarization-engineered AlGaN last quantum barrier for efficient deep-ultraviolet light-emitting diodes
摘要： The AlGaN-based deep-ultraviolet light-emitting diodes (DUV LEDs) has been identified as a prospective mercury-free UV source. However, the observation of severe electron overflow and low hole injection efficiency in the conventional DUV LED deteriorates the device performance, attributing to the downward band bending as a result of the strong polarization-induced electric fields between the last quantum barrier (LQB) and the electron blocking layer (EBL). In this study, a composition-graded AlGaN layer with linearly increasing of Al composition from 0.5 to 0.65 is proposed to act as the LQB, replacing the conventional flat LQB to reduce the effective barrier height for hole injection while improving the electron blocking ability. Hence, a considerable enhancement of the output power can be obtained. Moreover, further investigations show that the thickness of graded LQB determine the band bending in the LQB and thus significantly suppress the electron leakage, eventually leading to a boosted output power. The thorough investigation on the LQB could pave the way towards the realization of efficient DUV LEDs of the future.
关键词： electron blocking layer,ultraviolet light-emitting diodes,light output power,polarization field,graded last quantum barrier
更新于2025-09-23 15:19:57
-
Threshold decrease and output-power improvement in dual-loss Q-switched laser based on few-layer WTe<sub>2</sub> saturable absorber
摘要： A dual-loss Q-switched laser was realized by applying a home-made 2.5 nm-thick WTe2 to an acoustic-optic (AO) modulated laser. Besides conventional pulse compression, the participation of WTe2 could obviously improve the average output power by 29.6% and reduce the laser threshold by 20%, even with the introduced 8% nonsaturable loss. The average-output-power improvement and pulse compression in this dual-loss modulated laser resulted in a 113.7% increase of peak power. According to the measured spectra of laser and photoluminescence of WTe2, the laser-induced excitonic light-emission may be the reason of this laser gain.
关键词： WTe2 saturable absorber,laser threshold decrease,pulse compression,output-power improvement,dual-loss Q-switched laser
更新于2025-09-23 15:19:57
-
Enhanced Power Output from the PV with Low Input Ripple DC-DC Converter
摘要： The primary objective of Maximum Power Point Tracking (MPPT) for PV systems connected to a low-voltage DC grid is to extract the maximum possible power output from the PV array. Normally high-frequency switched mode power converters are employed to track the maximum power. These converters, however, impose switching frequency voltage ripple on the PV output. This causes fluctuation around the Maximum Power Point (MPP) and results in power loss. These losses can be reduced using electrolytic capacitors, however, the electrolytic capacitors’ lifespan is relatively shorter than that of a PV panel. In this paper, an interleaved boost converter is used to reduce high-frequency voltage ripple introduced on panel. Hence, smaller values of longer lifespan capacitors such as film capacitors will be sufficient to curtail the smaller ripple. Moreover, film capacitors are selected based on voltage ripple. Analysis was carried out for calculating voltage ripple imposed on PV module to select input filter more precisely. In addition, reduction in the voltage ripple is calculated quantitatively and is compared with that of a conventional boost converter. Enhanced power output from the PV panel is mathematically proven and experimentally demonstrated.
关键词： photovoltaic panel,switching frequency voltage ripple,PV output power,electrolytic capacitors,film capacitor,maximum power point tracking (MPPT),interleaved boost converter (IBC),low-voltage dc grid,DC-DC converter,photovoltaic (PV) system
更新于2025-09-19 17:15:36