关于平行线定向耦合器匹配隔离公式的一点注记

推导出平行线定向耦合器一般情况下的完全匹配公式与完全隔离公式,给出了完全匹配与完全隔离两种状态可同时实现的充要条件。     

有限长单线大地回路间互阻抗的计算方法

本文研究了有限长平行线路间互阻抗的表达式,其表达式为无量纲量aa和al的函数。为了比较按有限长线路公式计算的互阻抗与按无限长线路公式计算的互感阻抗的差异,进行了数字计算。计算结果表明:计算互阻抗时,可根据aa和al值的大小选择计算公式。在大多数情况下,仍可用无限长线路公式计算互阻抗。在大地电阻率高的地区。平行接近长度短的有限长线路,其互阻抗按有限长线路公式计算。     

射频识别系统中的四元振子天线分析

介绍用于射频识别系统中的一个半波天线阵的实际例子。天线由四单元半波振子组成，振子之间由双平行线馈电。给出了基本结构图，分析了带有接地板的天线方向图，阵列输入阻抗特性，以及阵列天线输入端驻波比频率特性。     

SAR图像主干道路自动提取算法研究

针对道路在高分辨率SAR图像中所具有的影像特征,提出了一种基于平行线对检测的高分辨率SAR图像主干道路自动提取算法.该算法以提出的新的平行线定义为核心,结合Marr视觉理论,使用自下而上的控制策略,对高分辨率SAR图像依次进行低层次的边缘检测(基于ROEWA算子)、中层次的道路特征结构化(平行线对检测)以及高层次的道路识别(路段生长、连接及去除伪道路),并在实验中给出了相应的算法演示结果图.实验结果表明,该算法能够准确有效地提取和定位高分辨率SAR图像中的主干道路.     

平行线耦合微带滤波器精确设计及去嵌入测试

平行线耦合滤波器是广泛应用于微波射频前端系统中的重要器件,为了解决加工误差引起的平行线耦合微带滤波器的频率偏移效应,提出了圆角化的设计方案,即对平行线耦合滤波器的开路端采用圆角设计方案替代传统的长度补偿方案,为了避免相邻平行线宽度不同导致的不连续性,将各阶长度和宽度非常接近的平行线设置为相同长度和宽度,给出了预调整设计参数的流程,通过传输线校准,实测获得了34ＧＨｚ滤波器去嵌入效应后的频率响应,带内插损3ｄＢ,带内波动小于 1ｄＢ,带宽3.8ＧＨｚ,测量结果与仿真吻合。     

双绞传输线电磁兼容特性的FDTD分析

将曲线坐标系中的时域有限差分法（FDTD）拓展到空间为任意媒质情形，然后针对双绞传输线的特殊结构综合运用曲线坐标系、圆柱坐标系、旋转坐标系和子域连接法进行空间网格划分、FDTD建模，并通过求解双绞传输线和平行传输线的特性阻抗对该建模的准确度进行了验证，最后在空间线源激励下对双绞线和平行线的电磁兼容特性进行了比较，可以看出双绞线对空间电磁场的耦合能力远远低于平行线。     

给定平面内直线度误差精确计算方法

本文证明了最小包容区域的存在性与唯一性，提出了一种新的寻找最小包容平行线的方法--逐次旋转逼近法。并给出了求解步骤。     

三平行线阵中基于改进传播算子的二维DOA估计方法

提出了一种三平行线阵中基于改进传播算子的二维波达方向估计方法。该方法针对三平行阵列的结构特点,利用三平行线阵中两个相互垂直的双平行线阵,分别构造一个扩展传播矩阵,求得旋转矩阵。然后根据三平行线阵的特性,对分别得到的旋转矩阵进行配对。最后利用配对后的旋转矩阵,联合估计信号的方位角和俯仰角。该方法当俯仰角在70°~ 90°之间时不会出现角度估计失效问题,充分利用了所有阵元信息,提高了角度估计性能,而且具有更低的计算复杂度。仿真验证了提出方法的有效性。      

空中巡逻战斗机搜索效能研究

为评估战斗机执行空中巡逻任务时的搜索效能,针对水平面内常采用的交叉线与双平行线搜索方式,在拟定假设条件和效能指标的基础上,推导出直线段搜索与转弯段搜索的计算公式,建立了两种航线的搜索效能模型.计算了战斗机在典型任务下按交叉线与双平行线对目标的搜索概率,对比了两种航线的搜索效能,分析了战斗机的飞行参数、设备参数以及任务参数对搜索效能的影响规律及产生原因,据此给出合理建议.     

浅谈量本利分析在电视台的应用

本文利用量本利分析对电视台的成本进行了成本性态分析，建立了电视台量本利基本公式，利用基本公式及其变形公式对电视台费用、利润进行测算，对电视台相关因素进行敏感分析，认为量本利分析在电视台解决广告定价、销售量预测、成本费用控制、企业经营安全以及制定应对市场变化的策略等方面将大有作为。     

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.     

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.     

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.     

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.     

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.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.