基于损失度的天波雷达抗有源压制干扰能力评估

为解决有源压制干扰条件下天波雷达抗干扰能力的定量评估问题,分析了用于天波雷达的压制干扰类型和天波雷达抗压制干扰措施,提出了发现概率损失度和探测区域损失度两个评估指标度量天波雷达抗有源压制干扰能力。基于时域处理、波束形成、换频等抗干扰措施的定量描述模型,推导出综合信干比方程,并结合信噪比方程、发现概率计算式和有效探测区域面积计算式建立了评估指标的计算模型。仿真分析了典型对抗条件下天波雷达的抗干扰能力,结果表明：天波雷达具有较强的抗有源压制性干扰能力,抗旁瓣干扰能力强于抗主瓣干扰。     

雷达抗有源压制性干扰性能评估研究

本文分析了有源压制性干扰的特点以及对雷达的影响,建立了评定雷达抗有源压制性干扰的综合指标,给出了回波能量损失系数的定义式,对传统的雷达综合效能评估方法进行了修正,建立了修正的雷达综合效能评估模型,并给出了雷达抗干扰效果评估的方法和步骤。     

雷达抗有源压制性干扰综合效能评估

雷达抗干扰效能评估是雷达作战效能评估的一个重要环节。通过对雷达在有源压制性干扰条件下特点的研究,提出了评定雷达抗有源干扰性能的综合指标,建立了雷达综合抗干扰能力评估模型,并给出了雷达抗干扰效能评估的一般流程。     

舰炮跟踪雷达抗干扰性能评估准则与指标研究

介绍了欺骗式干扰的作用原理、分类和雷达抗干扰技术,提出了舰炮跟踪雷达抗有源欺骗式干扰性能评估准则以及指标．为靶场开展舰炮雷达抗干扰性能试验与评估提供了参考。     

雷达系统抗压制型干扰效果的评估

本文应用效率准则,首先分析选取典型的电磁干扰环境并将其分类,为雷达系统的使用环境提供一个标准。 其次,根据雷达分系统中受压制型干扰影响的战术性能指标给出雷达分系统抗干扰性能指标体系,以便衡量雷达分系统的抗干扰能力。然后给出抗干扰指标的临界值体系的概念及建立方法,并由此给出雷达分系统抗压制型干扰的评价因子及雷达系统抗压制型干扰的评价因子——有效度的概念及算法,完成对机载火控雷达抗压制型干扰性能的评估。     

雷达组网抗复合干扰能力动态评估研究

为解决雷达组网系统抗干扰能力难以进行有效分析和评估的问题,基于复合压制干扰模式的机理分析,构建了组网系统抗压制干扰能力评估指标体系,运用仿真模拟法和灰色关联度评判法,对组网系统抗复合压制干扰能力进行了动态评估研究。对四种组网方案在复合压制干扰模式下的抗干扰能力进行了动态仿真分析和评估,仿真结果验证了评估指标及评估方法的可行性,表明雷达组网系统的抗干扰能力与雷达部署方式及数据融合规则密切相关,这与实际抗干扰试验的结论是相符的。     

2010雷达组网抗复合干扰能力动态评估研究

为解决雷达组网系统抗干扰能力难以进行有效分析和评估的问题,基于复合压制干扰模式的机理分析,构建了组网系统抗压制干扰能力评估指标体系,运用仿真模拟法和灰色关联度评判法,对组网系统抗复合压制干扰能力进行了动态评估研究.对四种组网方案在复合压制干扰模式下的抗干扰能力进行了动态仿真分析和评估,仿真结果验证了评估指标及评估方法的可行性,表明雷达组网系统的抗干扰能力与雷达部署方式及数据融合规则密切相关,这与实际抗干扰试验的结论是相符的.     

航空武器仿真中雷达干扰效果评估模块

分析了有源干扰、无源干扰分别采取压制式干扰、欺骗式干扰对对空雷达的影响途径。从基于雷达干扰方程的功能仿真角度出发，研究了航空武器论证仿真系统中雷达综合干扰效果评估模块的各种具体数学模型，分别讨论了对搜索雷达、跟踪雷达的有源干扰和无源干扰效果模型的建立。     

火控雷达抗压制性干扰指标及其相关性分析

火控雷达抗有源压制性干扰的性能评估是现代雷达性能评估的一个重要方面。作为雷达抗干扰性能评估的基础,抗干扰指标从根本上决定了评估工作的有效性和可靠性。首先介绍了有源压制性干扰的作用特点,分析总结了抗压制性干扰的指标集;然后通过理论计算与公式推导的方法,验证了抗压制性干扰指标间存在着等效性与可替代性的特点,获取了完备性好、可测性高的基础指标;在此基础上提出了以"自卫距离"和"可见度因子"两个指标来度量火控雷达的整体抗压制性干扰性能的评估思路,大大降低了性能评估实验的组织实施成本和复杂度,为火控雷达抗干扰性能评估奠定了基础,对靶场试验也具有一定的指导意义。     

相控阵雷达抗混合干扰算法研究

针对复杂环境中包含强压制式干扰与欺骗式干扰的混合干扰导致雷达抗干扰能力下降且目标检测不准确等问题,提出了一种基于旁瓣相消算法的抗混合干扰方法。通过分析相控阵雷达抗干扰技术的特点,发现将旁瓣相消算法可抑制压制式干扰的原理应用到各辅助通道信号传输过程中,能解决欺骗式干扰因压制式干扰功率过大而被淹没的问题,达到旁瓣匿影有效对抗欺骗式干扰的目的。通过仿真分析可知,该方法可有效降低混合干扰信号对雷达目标信号的影响,提高混合干扰环境下目标检测性能。      

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

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.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.