反射面天线馈源喇叭边缘照射电平的分析

反射面天线设计的关键就是通过选择合适的喇叭馈源边缘照射电平以追求天线的高性能（增益,旁瓣电平, 效率等）。本文主要利用实例验证了标准反射面天线馈源喇叭的优选边缘照射电平,分析了赋形反射天线馈源喇叭的优选 边缘照射电平,给出了标准反射面和赋形反射面在设计中各自馈源喇叭的优选边缘照射电平。从而可以在设计工作中对 于不同形式的反射面天线有针对性的设计馈源喇叭的边缘照射电平。     

基于NURBS建模的椭圆波束赋形天线设计

基于非均匀有理B样条曲面建模,提出一种低剖面椭圆波束赋形天线设计方法。利用馈源喇叭的辐射方向图和主反射面口面场分布函数,对φ=0°面的主副反射面曲线赋形,计算任意φ平面的主副反射面赋形曲线,利用非均匀有理B样条曲面建模技术对主副反射面建模并用全波仿真软件进行仿真优化。仿真结果表明,用该方法设计的椭圆波束天线在12.5 GHz和14.5 GHz时效率分别为67.82％和65.38％,第一副瓣电平均小于-14 dB,该天线实现了低剖面和高效率的优良性能。     

一种X波段多极化椭圆波纹喇叭设计

针对当反射面天线大宽高比并要求多极化转换时，宜选择椭圆波纹喇叭作为馈源的需求，在详细研究径向槽波纹喇叭天线设计方法的基础上，采用波纹槽深渐变的方法，利用HFSS软件设计一种X频段椭圆率大于2的带正交模的椭圆波纹喇叭。实测结果表明，该喇叭具有驻波低、交叉极化抑制度高和良好的双极化波瓣等化性等优点，可满足多极化反射面天线对馈源的需求，具有较高的工程应用价值。     

一种重新赋形副反射面的环焦天线设计

首先针对相同口径的环焦天线主反射面通用化需求,对双反射面天线的发展背景和环焦天线优点及赋形机理进行了简要介绍,然后提出了一种在不改变环焦天线的主反射面曲线的基础上,改变馈源照射角和重新赋形环焦天线副反射面曲线的设计方法,最后依据提出的设计方法给出了设计仿真计算,计算结果满足工程需求,避免了天线主反射面重新开模具,实现了环焦天线主反射面通用化,大大降低了天线的生产成本。     

一种星载通信混合反射面天线的设计方法

为了使星载通信天线产生1个赋形波束覆盖服务区,同时产生1个固定点波束和1个有限扫描点波束,该文提出一种由2个赋形反射面和3个馈源组成的混合反射面天线。该天线是以赋形主反射面共用为基础,等效为2副单馈源单偏置反射面天线和1副双偏置格里高利型赋形反射面天线,分别产生赋形波束、固定点波束和有限扫描点波束。通过对一副口径为1.2 m的天线各个波束进行仿真实验,赋形波束在Ku收、发频段时波束覆盖区边缘(EoC)方向性系数为27.5 dBi,固定点波束在C收、发频段时天线口径效率高于70%,通过将赋形副反射面及对应馈源横向偏焦实现Ka收、发频段的点波束在服务区内外的扫描。仿真结果表明,该混合反射面天线可实现C/Ku/Ka频段的同时通信任务。     

一种快速稳健的致密焦面阵列馈源设计方法

致密焦面阵列馈源(DFPAF)融合了多喇叭多波束馈源和相控阵列馈源(PAF)的特点,与多喇叭多波束馈源和常规相控阵列馈源相比较,它可以同时提供更多的固定赋形波束进一步拓宽视场。在射电天文、雷达、电子侦察和卫星通信等领域引起了极大的关注。由于其阵列结构与常规阵列馈源不同,导致设计方法也具有特殊性,因此近年来展开了对其设计方法的研究。该文充分利用反射面天线的固有特性,并结合阵列天线理论,提出一种可以快速、稳健地设计致密焦面阵列馈源的方法,给出了设计原理和设计结果,并和最具代表性的多喇叭多波束馈源进行了性能对比分析,为设计致密焦面阵列馈电的大型反射面提供理论和数据参考。     

赋形波束双弯曲反射面天线远场波瓣计算

针对赋形波束双弯曲反同天线出现条带相交情况，推导了按新坐标计算反射面天线远场波瓣公式，消除了条带相交区域的复复计算，解决了一般情况下赋形波束双弯曲反同天线的波瓣计算问题，提高了设计精度。文中还给出了设计实例和计算测试结果。     

宽角扫描赋形对称单反射面天线的优化设计

为满足宽角扫描的要求,基于几何光学理论对一种对称单反射面天线进行了赋形设计。以扫描口径面上射线路径的方差为目标函数,采用Powell方法极小化该函数,最终确定出了反射面的方程、特定扫描角度下的馈源位置以及馈源对反射面的照射区域,实现了天线扫描工作时的最小增益损失和最高口径利用效率。分析结果表明,所设计的单反射面天线在宽角扫描范围内,方向图无大的畸变,增益损失很小,副瓣电平达到了设计要求。本文赋形方法为宽角扫描双反射面天线的赋形设计奠定了基础。     

Ka 波段紧缩场天线的设计

设计了一个Ka 波段紧缩场天线。馈源设计结合角锥喇叭在反射面边缘照射电平下降快与波纹喇叭波瓣宽度宽的特点,通过给角锥喇叭加扼流套的改进设计来实现对反射面的照射。反射面采用锯齿型边缘来降低边缘的绕射作用,并进一步在无法加工锯齿部位贴附三角形吸波材料来减小绕射对静区特性的影响。暗室内采用平面测量结果表明,Ka 波段紧缩场天线静区特性满足设计指标要求。     

一种含误差的双弯曲反射面天线的新建模方法

提出了一种新的双弯曲反射面天线的建模方法,在拉格朗日插值和三次样条插值的基础上进行滑动平均,建立了具有馈源三维实体的含误差的双弯曲反射面天线模型,充分考虑了反射面模型的精度和光滑性,基于FMM给出了天线反射面存在不同加工误差和馈源安装误差情况下的赋形反射面电性能的分析,并比较了仿真结果与测试值,二者吻合性良好。结果表明:该建模方法有效,计算结果可靠,对误差设计和降低制造成本具有重要的参考价值。     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

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.     

Preparation and Characterization of TaN ALD Precursors

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.     

Electronic Structure of Semiconductor Nanocrystals

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

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.