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利用基于时域有限差分法(FDTD)的电磁仿真软件XFDTD,研究了核电磁脉冲与开孔腔体的耦合规律。分析了不同极化方向的核电磁脉冲入射时,矩形孔洞长宽比对耦合特性的影响;讨论了核电磁脉冲照射下,腔体谐振和孔缝与腔体的耦合谐振现象;给出了腔体内部电场分布的截面图,讨论了核电磁脉冲入射时腔体内外电场的空间分布情况。研究结果表明:当核电磁脉冲的极化方向与开孔矩形短边平行时,耦合的电场强度比正方形开孔时的要大,且长宽比越大,耦合的电场强度越大;当核电磁脉冲的极化方向与开孔矩形长边平行时,耦合的电场强度比正方形开孔时的小,且长宽比越大,耦合的电场强度越小。极化方向与矩形开孔短边平行时,腔体内产生了腔体谐振和孔缝与腔体的耦合谐振,开孔尺寸的变化会引起谐振频率的偏移;极化方向平行于长边时无明显电磁谐振发生。核电磁脉冲对屏蔽体内的影响主要局限于开孔附近。 相似文献
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电磁脉冲作用于屏蔽腔内的微带线电路的过程十分复杂。目前已有的研究存在局限,缺少将场分析与电路分析结合起来的研究方法。通过一个混合模拟方法计算了电磁脉冲辐照下的含屏蔽腔的微带线电路上的耦合电压。该方法通过建立腔体与微带线的电磁拓扑模型,利用BLT方程计算得到电磁脉冲在微带线上的耦合电压,结果表明电场强度为1 000 V/m的电磁脉冲会在微带线终端产生1.5 V左右的耦合电压。通过电路仿真软件仿真计算了外辐射场对电路工作状态造成的影响,外辐射场在300 V/m时会影响信号放大电路的正常工作。 相似文献
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罗学金 《太赫兹科学与电子信息学报》2017,15(4):684-689
为了确定电子系统的电磁脉冲(EMP)易损性并设计能承受电磁脉冲(EMP)威胁的电子系统,研究电磁脉冲(EMP)特性和电磁脉冲(EMP)耦合进入元件和电子系统的能量,以及电子系统战术性能降级所产生的影响。介绍了封闭腔体内抗强电磁干扰的小型电磁场传感器的设计过程,对该传感器的等效电路、匹配网络和测量方法进行了详细的理论计算分析。也对研制过程和实际应用情况进行了介绍。得到了小型腔体内的内电磁脉冲(IEMP)环境参数。为电子系统提供了抗电磁干扰以及加固设计的参考数据。 相似文献
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为提高电子设备及系统在复杂电磁环境下工作的稳定性,应用时域有限差分方法对不同脉宽电磁脉冲通过带有不同形状(方形环,圆环,矩形环)环形孔缝屏蔽腔体的耦合规律进行了分析.研究结果表明:电磁脉冲通过环形孔缝耦合现象明显,其通过圆环的耦合能量最小;对于矩形环,当入射波极化方向与环形孔缝的短边平行时,若矩形环孔缝纵横比越大,则耦合能量也越大,当极化方向与短边垂直时,则纵横比越大,耦合能量越小;入射电磁脉冲脉宽越短,电磁脉冲越容易耦合进入环形孔缝;腔体壁的反射及谐振会增强耦合效应. 相似文献
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电磁脉冲对带孔缝腔体的耦合特性 总被引:8,自引:0,他引:8
利用时域有限差分方法(FDTD)研究了电磁脉冲对带孔缝导体腔的耦合特性。为减少存储空间而采用非均匀网格法,分别对腔体上开有不同形状(正方形、长方形)和不同数目孔缝时的耦合效应进行分析。结果表明,在孔洞面积相同的情况下,电磁脉冲对正方形孔洞的耦合能量较小;而对长方形,当脉冲的极化方向与孔洞短边平行时,耦合能量最大;此外,把单个孔洞分成总面积不变的多孔洞后,耦合能量减小;同时,在保持通风面积不变的情况下,将原本开在一层屏蔽板上的孔缝交错地开在两层板上,能够明显改善屏蔽效果。 相似文献
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为了研究电磁脉冲(EMP)强度和分布与激光参量、靶体材料、结构等之间的关系,采用靶室内部的超小B-dot天线对强激光打靶过程中产生的电磁脉冲进行了测量,分析了不同辐射方位的脉冲强度,同时探讨了靶体支撑杆为绝缘体和导体两种情况下的电磁辐射行为。结果表明,不同方向和不同靶杆测得的电磁脉冲明显不同,如在法线方向的电磁辐射达到20V,导电靶杆最大达到22V的辐射,说明强激光打靶诱导的EMP具有很强的极化方向,并且在导体靶杆情况下,能够产生更强的电磁辐射。该研究有助于揭示激光打靶产生的EMP在靶室内部的传输极化特性以及其强度与靶杆导电性的关系。 相似文献
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为提高系统抗强电磁脉冲毁伤能力,采用时域有限差分法(Finite Difference Tim
e Domain,FDTD)和通用电路仿真器(SPICE)相结合的协同仿真方法,以圆柱腔内由单导线、
双绞线、普通双线和同轴线组成的线束为研究对象,重点研究了导线类型、导线间距、捆扎
和RC滤波电路对耦合特性的影响。结果表明:耦合系数受腔体和传输线的双重影响,同轴线
耦合系数较其他两类线缆降低约40 dB;线间相互屏蔽是捆扎降低耦合系数的主要原因
;随着导线间距增大,耦合系数幅值增大;RC滤波电路是降低电磁耦合的有效手段。所得结
论对电子系统进行抗电磁脉冲加固具有重要意义。 相似文献
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为了解高功率电磁脉冲对电子系统的干扰与毁伤影响,利用基于Wigner鄄Ville 分布的时频分析方法对耦合进电子系统内部的电磁信号进行了特征分析。与单独的时域分析和频域分析相比,时频分析不仅能够得到信号的时域特征和频域特征,还能同时得到信号各频率分量随时间的变化情况。利用瞬态极化时频分析,进一步得到信号极化状态在时频域的分布。仿真结果表明,时频分析得到的结果更全面详细,可以根据时频分析得到的信号特征更加准确地指导电子系统的高功率电磁脉冲防护加固。 相似文献
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Meihua Shen Wilfred Pau Nicolas Gani Jianping Wen Shashank Deshmukh Thorsten Lill Jian Zhang Hanming Wu Guqing Xing 《半导体技术》2004,29(8)
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration. 相似文献
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White organic light-emitting devices based on fac tris(2- phenylpyridine) iridium sensitized 5,6,11,12-tetraphenylnap -hthacene 总被引:1,自引:0,他引:1
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V. 相似文献
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Complete approach to automatic identification and subpixel center location for ellipse feature 总被引:1,自引:0,他引:1
XUE Ting WU Bin SUN Mei YE Sheng-hua 《光电子快报》2008,4(1):51-54
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction. 相似文献
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In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy. 相似文献
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High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center. 相似文献
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Credence Systems Corporation 《半导体技术》2004,29(9)
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V. 相似文献
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This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors. 相似文献
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YUXiao-hua XIANGYu-qun 《半导体技术》2005,30(2):30-32,37
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB. 相似文献
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It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV). 相似文献