抗箔条质心干扰的一种方法

为提高反舰导弹末制导雷达抗箔条的能力,提出了一种基于小波变换的抗质心干扰方法.经仿真干扰数据检验,结果表明在一般情况下,对信干比(SDR)约为-5dB的质心干扰回波,该方法能够比较准确地探测出目标,且算法简单.     

用小波实现箔条噪声的消除

为了对抗反舰导弹的威胁,箔条这种具有多种优点的无源干扰技术被越来越广泛的应用,因此对其进行识别和消除的工作变得相当重要,而小波通过对信号进行多尺度细化分析,能有效地从信号中提取信息,并能放大雷达回波信号的局部细节,从而实现对舰艇和箔条假目标的识别和区分,并进一步去除箔条干扰。利用小波分析这种新兴的信号处理技术中的Mallat算法,完成对箔条噪声消除的计算机仿真。     

以波形相关识别箔条和军舰的FFT方法研究

自从1973年第4次中东战争中箔条干扰首次在舰艇上使用以来,箔条干扰已经被各国海军水面舰艇广泛装备和使用,并被证明是干扰反舰导弹末制导雷达的非常有效的手段。理所当然,战术反舰导弹抗箔条干扰技术成为各国电子战领域中共同关注的课题。本文将箔条及目标回波预处理后进行FFT变换,根据波形相关性的差异进行识别,并进行了硬件实现。     

反舰导弹抗质心干扰仿真研究

采取动态仿真的方法,对反舰导弹抗箔条质心干扰的全过程进行作战仿真,分析了在反舰导弹抗干扰过程中导弹威胁方向以及舰艇机动、作战海域的风速、风向等要素对导弹抗干扰效果的影响,获得了反舰导弹抗箔条质心干扰的作战使用原则,对反舰导弹成功突防箔条质心干扰具有指导意义。     

舰船箔条质心干扰建模与仿真

箔条质心干扰是舰船在受到反舰导弹攻击时重要的防御方式之一。介绍了舰船箔条质心干扰原理,然后构建了作战环境、舰船、箔条云、弹载雷达目标检测等模型,进行了仿真计算,对仿真数据进行了分析,给出了不同情况下箔条云最佳的布放距离和角度,使箔条干扰在对抗反舰导弹时能发挥最大效果。     

反舰导弹末制导雷达抗箔条干扰的一种方法

箔条干扰是当前反舰导弹末制导雷达面临的一件威胁极大的无源干扰。研究战术反舰导弹本制导雷达抗箔条干扰已成为各国电子战领域中共同关注的重要课题。本文针对飞航式导弹的抗箔条干扰问题，提出了一种基于波形软匹配的舰船目标特征检测新方法。并有实录数据对该方法进行了实验，实验结果表明：该方法具有较高的检测率，证明了该方法是有效的。     

基于小波变换的红外成像检测掠海飞行导弹研究

首先给出小波变换的算法原理;然后采用二维小波详细分析了低空掠海飞行反舰导弹目标的基本检测原理和检测方法;最后采用MatLab模拟得出了在强太阳光照射条件下低空掠海飞行反舰导弹目标的检测图像。仿真结果表明,利用小波变换方法能够较为有效地检测出强红外背景下的掠海飞行的导弹信息,并且具有较高的探测精度、能够满足探测预警实时性要求等优点。     

基于图像差分、小波变换和回归分析的近场反舰导弹探测

可见光面目标反舰导弹探测用于指挥火炮系统对逼近的反舰导弹进行跟踪射击。采用图像差分和小波变换可以准确提取信噪比接近于1的反舰导弹图像,通过特征一致性评估算法以及基于对运动轨迹一元线性回归效果的检验进一步对该反舰导弹图像进行判断。试验证明,提出的目标提取算法和探测算法可以在近距离用可见光图像探测与背景灰度接近的反舰巡航导弹目标,也适合于其他来袭导弹与飞机的近距离探测,具有较普遍的探测适用性。     

基于小波包变换和形态学的图像分割算法

数字图像分割技术是一种重要的提高计算机图文识别的手段.文章利用小波包变换去噪结合形态学方法提出一种数字图像阈值分割算法.依据该算法,首先施行小波包变换,去除图像中的噪声,然后利用形态学方法集合最佳阈值判别对图像进行分割.实验证明,本算法的分割效果较佳.     

提高大型水面舰艇干扰效果的方法研究

对大型水面舰艇防御现代反舰导弹来说,舰载有源干扰和传统的箔条质心干扰都遇到了很大困难。讨论了采用吸收型箔条、舷外有源诱饵、复合诱饵3种方法提高大型水面舰艇干扰效果的方法,并进行了应用分析。     

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.     

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.     

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.     

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.     

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.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

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.