新乡电离层总电子含量观测结果

本文对１９８１年１１月到１９９０年１２月期间新乡站（３５．３°Ｎ，１１３．８°Ｅ）利用偏振仪观测ＥＴＳ—Ⅰ卫星１３６ＭＨｚ信标法拉第旋转效应而获得的电离层总电子含量（ＴＥＣ）进行了一些统计工作》阐明了新乡地区ＴＥＣ每日最大值、最小值以及它们出现的本地时间等参量月中值的变化，比较了太阳黑子高、低年ＴＥＣ变化的差异，以及与太阳黑子数和耀斑的关系，并对此作了初步讨论。     

海口VHF信号幅度闪烁观测结果

本文介绍了海口地区１９８９年１２月－１９９０年１２月期间，ＥＴＳ－Ⅱ卫星ＶＨＦ信号幅度闪烁观测结果。表明闪烁主要出现在二分季月份的夜间，９月份出现率最高，１２月１月出现率最低；多为电离层泡引起的强烈闪烁。     

最新实用中国上空卫星电视频道表

卫星名称静止轨道位置电视台名称 下行频率ＭＨｚ 电视制式 极化方式伴音频率或数字压缩参数备注及卫星所属国Ｉｎｔｅｌｓａｔ-70 1(国际 70 1)　 180°Ｅ美国ＴＢＮＲＦＯ波利尼西亚泰国 5频道、ＳＢＮＣａｎａｌ 喀里多利亚、波利尼西亚ａｂｃ新闻传送3 7643 7723 92 240 951113 5ＰＡＬＰＡＬＰＡＬＰＡＬＮＴＳＣＲＲＬＬＶ7/82 9.90 03 /44 .5 663 /42 1.2 0 03 /42 7.5 0 06.8Ｉｎｔｅｌｓａｔ-70 2 (国际 70 2 )　 172°Ｅ美国ＲＦＯ波利尼西亚 40 2 7ＰＡＬＬ 3 /44 .5 66ＰＡＮＡＭＳＡＴ -2 (泛美 2号 )　 169°Ｅ美国中央电视台…     

高性能PtSi凝视红外焦平面列阵的研究与进展

本文叙述了国内外ＰｔＳｉ凝视红外焦平面列阵（ＦＰＡ）的研究发展状况。详细介绍了提高ＰｔＳｉ肖特基势垒探测器（ＳＢＤ）灵敏度的研究工作。这些ＳＢＤ工作温度约为８０Ｋ，应用于中红外波段（３～５μｍ）。象素数达５１２×５１２，１０２４×１０２４的凝视列阵已见报道。ＰｔＳｉＳＢＤＦＰＡ能在３００Ｋ实现热成象，其噪声等效温差（ＮＥａｒ）达到０．０３Ｋ。文中还介绍了我国研制的１２８×１２８元，２５６×２５６元ＰｔＳｉ凝视红外焦平面，并讨论了凝视ＦＰＡ的设计选择，最后对其特性进行了简要总结。     

卫星电视与其节目台参数及部分接收实例(上)

本文介绍的是亚太地区上空几颗主要电视卫星的参数及其接收节目台的参数,接收节目台主要以中国中央台及省台播出的节目为主。 １．１００．５°Ｅ亚洲二号（ＡＳＩＡＳＡＴ—２） （１）亚洲２号卫星参数 发送日期：１９９５年 １１月 ２８日。 使用寿命：１５年。 隶属单位：中国国际信托投资公司、英国大东电报局、香港和记黄浦有限公司共同投资拥有。 用途：通信（含电视）。 转发器：Ｃ波段２４个,Ｋｕ波段９个。 带宽：Ｃ波段中 ２０个转发器带宽为 ３６ＭＨＺ,４个带宽为７２ＭＨｚ,Ｋｕ９个带宽为５４ＭＨｚ。 接收天线口径（Ｄ…     

卫星电视单星、双星接收方法和实例

一、 单星接收方法和实例 １． 接收亚洲３Ｓ号卫星 该星定点在１０５．５°Ｅ,中心波束ＥＩＲＰ为３６ｄＢＷ,在Ｃ波段上可收到凤凰中文台、音乐台、体育台和合家欢台,其接收方案及设备配置如图１。 如果用户的电视机是多制式或接收机有制转功能的可以不用另配转制器。 ２．接收亚洲２号卫星 该星定点在１００．５°Ｅ,中心波束功率Ｃ波段ＥＩＲＰ为３９ｄＢＷ,Ｋｕ波段ＥＩＲＰ为５２ｄＢＷ,其节目内容见表１。 （１） 接收Ａ类和Ｂ类节目方案 方案如图２所示。此方案可接收国内外２０多套电视和广播节目。天线选用优质产品,最好是…     

国际卫星组织的DAMA网络

国际卫星组织的ＤＡＭＡ网络○井超截至１９９７年４月，国际卫星组织（ＩＮＴＥＬＳＡＴ）陆续建成了大西洋、印度洋、太平洋３个ＤＡＭＡ网络的基本骨架，即每网建成两个网络管理控制中心（ＮＭＣＣ）。其中，北京中标成为太平洋东经１７４°７０１卫星ＤＡＭＡ网中的一...     

ISDN和中继通信用的卫星通信系统DYANET—Ⅱ（下）

ＩＳＤＮ和中继通信用的卫星通信系统ＤＹＡＮＥＴ—Ⅱ（下）ＴｏｕｒＯｔｓｕ等４ＤＹＡＮＥＴ—Ⅱ的系统结构４．１网络结构ＤＹＡＮＥＴ—Ⅱ由一颗通信卫星、用户站（ＵＥＳ）、基站（ＢＥＳ）、一座控制站（ＣＥＳ）、一个卫星信道控制单元（ＳＣＵ）和一个卫星中转单...     

宽带接入网技术及其应用

４无线宽带接入技术无线接入系统主要分两大类：①固定无线接入。包括点到点微波通信、ＸＭＤＳ［包括本地多点分配业务（ＬＭＤＳ）和多路多点分配业务（ＭＭＤＳ）］、甚小孔径终端卫星（ＶＳＡＴ,工作波段为Ｋｕ和Ｃ,地面站天线一般小于２．４米）和卫星直播系统（ＤＢＳ,工作波段为Ｋｕ和Ｃ的同步卫星。地面站天线一般大于６米）等;②移动无线接入。包括：无线ＬＡＮ、无绳电话、集群系统、蜂窝移动通信（ＧＳＭ和ＣＤＭＡ）、同步卫星移动通信系统和低轨卫星移动通信系统。其中移动无线中的无绳电话、集群系统、ＧＳＭ等都属于窄带…     

局部网络中的TOKEN—PASSING技术

本文通过对ＴＯＫＥＮ－ＰＡＳＳＩＮＧ协议与ＣＳＭＡ协议的比较，说明ＴＯＫＥＮ－ＰＡＳＳＩＮＧ技术克服了ＣＳＭＡ协议的不足，从实例中阐述了该技术在局部网络中的重要地位及其优点。     

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.