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1.
Optical gates based on switchable material have become a focus of investigation. The present study designs an optical gate that uses DNA transmission lines and developed for Feynman and Toffoli reversible gates. It is shown that the implementation of a transmission line such as Ag/DNA/Ag produces a structure with high-quality switching. The switching characteristics of DNA were considered when designing the basic transmission line. The “On” mode is assumed for DNA with low conductivity. As conductivity increases, the line switches to the “Off” mode. A conceptual design is proposed in the present study for Feynman and Toffoli reversible gates for an optical regime at 300 THz based on DNA switching. A conceptual model is developed with an Ag/DNA/Ag transmission line controlled by changing the DNA bias. This transmission line provides a “Yes” gate, which is necessary for a reversible gate. The full wave time domain method was used to model the optical gates. The current work discusses how a DNA memristor can be used to design a compact reversible gate having a simple structure and high switching quality for use in optical systems.  相似文献   

2.
 分析了周期性电容盘片加载的同轴线的传输特性,并将其应用于四分之一波长线谐振腔,利用传输线理论和数值模拟两种方法分析了这种腔体的谐振特性,得到了谐振频率、Q值与盘片半径、盘片个数间的关系,并论证了这种方法在减小腔体尺寸方面的可行性及在一台质子回旋加速器腔体中的应用。  相似文献   

3.
A novel 35GHz 3dB power divider using coupled transmission line is presented. Unlike conventional Wilkinson divider circuit, only the 50 transmission lines are used in the design. The impedance matching can be achieved by coupled transmission line even mode characteristic impedance. The predicated and measured performances agree well.  相似文献   

4.
Transmission line-based multi-channel solid state NMR probes have many advantages regarding the cost of construction, number of RF-channels, and achievable RF-power levels. Nevertheless, these probes are only rarely employed in solid state-NMR-labs, mainly owing to the difficult experimental determination of the necessary RF-parameters. Here, the efficient design of multi-channel solid state MAS-NMR probes employing transmission line theory and modern techniques of electrical engineering is presented. As technical realization a five-channel ((1)H, (31)P, (13)C, (2)H and (15)N) probe for operation at 7 Tesla is described. This very cost efficient design goal is a multi port single coil transmission line probe based on the design developed by Schaefer and McKay. The electrical performance of the probe is determined by measuring of Scattering matrix parameters (S-parameters) in particular input/output ports. These parameters are compared to the calculated parameters of the design employing the S-matrix formalism. It is shown that the S-matrix formalism provides an excellent tool for examination of transmission line probes and thus the tool for a rational design of these probes. On the other hand, the resulting design provides excellent electrical performance. From a point of view of Nuclear Magnetic Resonance (NMR), calibration spectra of particular ports (channels) are of great importance. The estimation of the π/2 pulses length for all five NMR channels is presented.  相似文献   

5.
文中论述了液氮(LN2)传输线的绝热结构设计,并对选择的传输线绝热类型进行了绝热分析。经过实验的验证,此传输线的结构设计是合理的,达到了理想的绝热效果。  相似文献   

6.
在进行感应电压叠加装置设计时, 为了使初级脉冲形成与传输系统产生的快前沿高压脉冲均匀耦合到次级传输线, 需要建立感应腔的二维电路模型对电磁波在角向传输线中的传播过程进行分析, 并基于电路计算结果优化设计角向传输线阻抗分布规律,使次级传输线中电流能够均匀分布。由于角向传输线结构复杂, 没有精确求解阻抗值的解析公式, 介绍了一种基于电报方程和瞬态电磁场仿真求解复杂结构传输线阻抗值的方法, 采用该方法对等宽度和变化宽度两种结构角向传输线阻抗值进行了评估。研究结果表明,相比于三平板传输线阻抗计算公式, 采用微带传输线阻抗计算公式对角向传输线阻抗值进行求解结果更加精确。  相似文献   

7.
 在传输线应用中,负载终端匹配设计是一个重要问题。用拉普拉斯变换方法严格求解Blumlein传输线的电报方程,研究在纯电阻负载和带分布参数负载情况下,波在传输线中的瞬态传输过程,得到了清晰的物理图像,结果与通常的行波传播分析法完全一致。  相似文献   

8.
阐述了EAST离子回旋加热天线传输线的结构设计。用有限元的方法对EAST离子回旋加热天线传输线内导体结构进行了分析,获得了内导体的受力情况。根据内导体的受力情况适当加大波纹管厚度和设计内导体支撑,通过ANSYS分析优化确定了波纹管的厚度和内导体布置的位置。此外,还计算了传输线的热损耗、热变形、电压驻波系数和最大功率容量,计算结果进一步验证了传输线结构的可行性。  相似文献   

9.
This paper describes the theoretical and experimental results of a novel leaky-wave antenna incorporating a homogeneous dielectric transmission line and radiating aperture into a single structure. The primary objective of this investigation is to demonstrate the ability to control aperture radiation by simply cutting slots into a metal-free dielectric transmission line. Experimental line source antennas with identical periodic slots were designed to operate in the 35 GHz frequency region. The successful performance of these antennas resulted in the design of a dielectric line source antenna with a symmetrical amplitude taper which provided a lower sidelobe level. The design represents a significant breakthrough in achieving affordable, low-loss, lightweight antennas in the millimeter wave region. The most significant applications for this type of antenna include radar surveillance and tactical missile-seeker terminal guidance.  相似文献   

10.
The design of nonuniform bilateral finlines on anisotropic substrates for millimeter wave applications is presented. The taper consists of a planar circuit with smooth variation of the slot width profile along the structure. The spectral domain method and Galerkin procedure are combined with the transmission line theory for studying the behavior of tapered bilateral finlines and evaluation of their design parameters. The influence of the substrate anisotropy on the propagation characteristics of these structures is also examined. This technique is general and can be applied to investigate a broad class of planar transmission line tapers.  相似文献   

11.
阳加速器水传输线及磁绝缘传输线的电路模拟   总被引:1,自引:1,他引:0       下载免费PDF全文
 根据阳加速器传输线的阻抗分区特性,建立电路模型,并对短路实验及丝阵内爆实验进行模拟。短路实验的模拟结果与实验测试结果非常接近;通过对丝阵具体条件的分析,合理地引入串联电阻,同样准确地模拟了丝阵内爆的传输线响应特性,并利用模型简单描述了丝阵内爆的一般特性。模拟结果表明,模拟方法正确有效、电路模型可用于变阻抗水传输线及MITL的设计分析及基本规律研究。  相似文献   

12.
Most transmission gratings in the x-ray region work with their first orders and dispersion is limited by the line density achievable with current fabrication technology. We present a novel design of a two-dimensional x-ray transmission grating. The grating works with higher dispersion using its second orders, and the influence from first and third orders can be suppressed. A grating according to the novel design is fabricated and its diffraction performance is tested in comparison with a traditional x-ray transmission grating with the same line density. The novel grating could be especially useful when high dispersion is desired while the fabrication of high-density gratings becomes more difficult.  相似文献   

13.
新型电感储能脉冲功率驱动源   总被引:1,自引:0,他引:1       下载免费PDF全文
提出了将传统单个储能电感利用传输线分隔成两部分的新型电感储能脉冲功率驱动源技术方案。理论分析表明,利用传输线电容的耦合延时作用,可有效对调制器输出脉冲波形进行整形,并且可以进一步提高能量转换效率,从而克服传统电感储能脉冲功率源输出波形质量差(类三角波波形)的缺点。基于该思想开展了实验研究,获得了电压约300 kV,电流约20 kA的电子束,并成功驱动S波段磁绝缘线振荡器获得了百MW量级的微波输出。  相似文献   

14.
王源  张立忠  曹健  陆光易  贾嵩  张兴 《物理学报》2014,63(17):178501-178501
随着器件尺寸的不断减小,集成度的逐步提高,功耗成为了制约集成电路产业界发展的主要问题之一.由于通过引入带带隧穿机理可以实现更小的亚阈值斜率,隧道场效应晶体管(TFET)器件已成为下一代集成电路的最具竞争力的备选器件之一.但是TFET器件更薄的栅氧化层、更短的沟道长度容易使器件局部产生高的电流密度、电场密度和热量,使得其更容易遭受静电放电(ESD)冲击损伤.此外,TFET器件基于带带隧穿机理的全新工作原理也使得其ESD保护设计面临更多挑战.本文采用传输线脉冲的ESD测试方法深入分析了基本TFET器件在ESD冲击下器件开启、维持、泄放和击穿等过程的电流特性和工作机理.在此基础之上,给出了一种改进型TFET抗ESD冲击器件,通过在源端增加N型高掺杂区,有效的调节接触势垒形状,降低隧穿结的宽度,从而获得更好的ESD设计窗口.  相似文献   

15.
This paper proposes a dual-band power divider operating at GHz frequencies and implemented by means of impedance transformers (also called inverters) based on lattice networks and transmission line sections. The dual-band functionality of the proposed device is achieved thanks to the composite right/left handed (CRLH) behavior of the impedance transformers, able to provide −90° and +90° phase shift at the first and second design frequencies, respectively, of the divider. By using such combination of transmission line sections and lattice networks, the characteristic impedance of the impedance transformers is roughly constant over wide bandwidths, with the results of broad operating bands. To demonstrate the possibilities of the approach, a prototype device is designed, fabricated and characterized.  相似文献   

16.
高功率开关是脉冲功率装置中的重要部件。介绍了2 MV激光触发多级气体开关的设计思路,给出了开关在强光一号装置上的的静态实验和触发实验结果。实验结果表明:开关的性能基本达到设计的要求;开关在低阻抗传输线中进行实验,面临传输电荷量大的问题,传输电荷越大,将导致更多的放电产物,从而使绝缘能力下降,直接影响开关的使用寿命。  相似文献   

17.
中国原子能科学研究院于1994年研究建成我国第一台医用强流回旋加速器CYCIAE-30及配套放射性同位素生产线, 目前为了增加气体靶以生产新品种医用同位素, 在原有束流输运线的基础上开展了束流输运系统的升级改造方案设计, 包括束流线的总体布局考虑和光学设计, 并根据束流光学设计的结果, 进行了新增束流线上电磁元件的设计. 在物理设计的基础上, 还进行了施工设计以及各分系统的加工、调试、安装, 并以物理设计得到的参数为依据进行了束流调试, 靶上得到的束斑与理论值有较好的符合, 满足设计要求.  相似文献   

18.
A systematical procedure for multilayer dielectric filter design is introduced here based on the transmission line model (TLMBCAD). By this procedure, low-pass, high-pass, and band-pass filters can be designed in the same way. The transmission line model works well and is time efficient not only for normal incidence of linearly polarized wave but also for oblique incidence wave with circular polarization. Design examples are given for low-pass and band-pass filters. Simulation results show that the method developed in this paper is valuable for the engineering design of multilayer dielectric filters.  相似文献   

19.
The design of a broadband 4-mm magic-angle spinning (MAS) X-(1)H/(19)F double resonance probe for cross-polarization (CP)/MAS NMR studies at 21.15 T ((1)H at 900 MHz) is described. The high-frequency (1)H/(19)F channel employs a new and efficient transmission line tuning design. The first (13)C CP/MAS NMR spectra recorded at 21.15 T have been obtained with this probe and exhibit the best S/N per milligram sample of hexamethylbenzene achieved so far for a 4-mm rotor.  相似文献   

20.
高仁璟  王国明  刘书田  唐祯安 《物理学报》2012,61(5):54103-054103
为研究具有特定频段的左手材料设计方法. 首先基于传输线理论构造了一种左手材料微观构型, 采用S参数反演法进行数值仿真和等效传输线模型分析, 说明了该构型在特定的尺寸条件下具有左手特性, 并分析了尺寸参数对左手性能的影响. 进而给出了在给定频率附近具有最大带宽、较小损耗的左手材料设计优化问题的数学模型, 并给出了设计实例. 数值设计结果验证了优化模型的适用性和正确性.  相似文献   

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