遥感卫星"夸父A"星地通信接收站布局建模与分析

面向实时接收遥感卫星"夸父A"连续对日观测数据的应用需求,提出"夸父A"卫星与地面单个固定接收站相对位置模型,在此基础上定量评估现有国内及海外站的接收效率,并进一步提出地面接收站全球布局的基本原则及其可行的优化方案.研究成果将为"夸父"计划星地数据通信系统的实施提供重要的技术参考.     

对地面某区域某时段连续覆盖的卫星轨道计算

为了对地面某一区域在未来某一时段连续覆盖,需要对在轨卫星变轨,并计算变轨后的卫星轨道参数。基于在轨卫星部分轨道参数(椭圆轨道a,i,e,圆轨道a,i)和t时刻星下点的位置坐标及卫星的地面高度,计算卫星的6个轨道参数,从而得到t时刻对星下点位置为中心的区域覆盖所需要的卫星轨道参数。利用t时刻卫星在J2000.0平天球坐标系3个坐标轴的位置与速度分量计算其卫星轨道参数。用STK卫星工具箱软件6.0高精确度轨道产生器仿真,输入所得的t时刻卫星轨道参数,运行STK 6.0得到的星下点位置与事先设置的星下点相距6.63 m,完全满足卫星对地面覆盖的需要。欲对该区域在t时刻以后的一段时间连续覆盖,所需要的卫星轨道参数可按共地面轨迹计算;通过STK 6.0高精确度轨道产生器对计算得到的卫星轨道参数进行仿真,验证了计算结果的正确性。     

卫星地面接收站使用调整经验谈

本文主要介绍卫星地面接收站站址的选择、卫星信号干扰的排除以及C波段、Ku波段卫星地面接收站的快速调整等.     

资源卫星接收站高分辨率实时快视处理

本文较系统地阐述了资源卫星地面接收站对遥感图像的高分辨率实时快视处理方法。文中提出了主要针对接收美国Landsat卫星TM数据的实时快视系统方案,其具有1024×1024显示的高分辨率,兼顾了多功能、低成本、简易性和对不同类型遥感数据快视处理的兼容性等特征,为我国已建的和即将兴建的资源卫星接收站配置实时快视系统提供了一条有效途经。     

关于“村村通”广播电视地面卫星接收站的安装及维护

党和政府对于农村广播电视的重视,使“村村通”广播电视地面卫星接收站的发展越来越快,了解必要的地面卫星接收站的安装及维护方法将更有利于“村村通”工程的建设.本文简单介绍了地面卫星接收站,叙述了“村村通”广播电视地面卫星接收站的安装、维护方法及安装维护过程中应注意的事项,以方便“村村通”工程中广大群众对地面卫星接收站的使用.     

遥感卫星接收控制软件分析与改进技术

简述了某遥感卫星地面接收站接收站接收控制系统组成和工作原理，介绍了软件系统结构的分析方法，提出了适应需求的改进方案，归纳了在改进过程中应注意的关键技术及解决措施。     

擅自安装和使用的卫星地面接收站再度泛滥亟待治理

对于卫星地面接收站的安装和使用,国家广电总局从未放松过管理.前几年,国家广电总局继与国家工商行政管理局等联合行文后,又在广电系统逐级签订了责任书,以切实加强对卫星地面接收站的管理,实事求是地讲,这对卫星地面接收站的擅自安装使用,确实起了不小的遏制作用.但最近一段时间,在一些地方,擅自安装、使用的卫星地面接收站越来越多.     

共地面轨迹移动卫星通信星座设计

本文从移动卫星地面轨迹的特点出发研究了一种共地面轨迹移动卫星星座的设计方法,并借助于计算机模拟和专业卫星通信工具软件对我国区域进行了设计,在选定轨道周期为1／4个恒星日,偏心率为0．158,轨道倾角为63．4°的情况下,4颗共地面轨迹卫星即可对我国大陆（北纬20°至55°）基本达到连续覆盖,平均仰角大于48°．     

卫星地面接收站的调试方法

近几年，随着广播电视事业的飞速发展，各省市的电视节目纷纷上星，地面接收站也越建越多。随着“三小站”和“村村通”工程的建设，我旗境内也建起了相当数量的卫星地面接收站。卫星地面接收站接收天线的调试是一个至关重要的技术问题,它直接影响到节目的接收质量。我根据以往的工作实践谈一下卫星地面接收站的调试方法。1 根据卫星的定点参数和接收地的经纬度计算出卫星地面接收天线的仰角和方位角。其中：B：地面接收站的纬度。A1：地面接收站的经度。A3：卫星定点位置经度。r：地球半径6378千米。R：卫星同步轨道半径42218千米。2 根…     

低轨卫星目标的角加速度分析

以A-E座架遥感信号接收站角跟踪系统作为研究对象，通过在接收站测量坐标系内对低轨卫星目标运动规律的描述，建立了遥感接收站角跟踪系统的角加速度动态模型，并对该动态模型进行了仿真分析。     

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.