磁性材料、超导材料和器件

TM27 U005UU79新型有机磁性材料及其在微波领域的应用/林展如,倪习“铭、赵见高(四川师范大学)11微波学报一1 999,15(4).一329一333与铁氧体相比,所合成的有机磁性材料在很宽的温度范围内(一2 71.5一120℃)电感和磁性能十分稳定、在甚高频和微波频段磁损耗小,重量轻,无需高温烧结,易热压成型,且有良好的抗辐照和抗自然老化性能,最适于制作100一3000MHZ频段的电子器件,它将填补铁氧体在甚高频及微波频段应用上受到一定限制的空白.图5表1参5(许)TM27、、00050080磁性行业的创新工程与可持续发展战略/李士根(南京电子技术研究所)刃电子工程…     

电子器件

Z98-51290-12 9907235微波铁氧体超导器件的发展远景[会]/潘永吉//第九届全国微波磁学会议论文集.—12～15(C)Z98-51290-107 9907236石英声表面波(SAW)谐振器的研制[会]/陈晓阳//第九届全国微波磁学会议论文集.—107～110(C)谐振器在通讯和信息处理中得到广泛的应用,它可作窄带滤波器,还可用作频率源关键部件,SAW 谐振器可以直接工作于甚高频和超高频段,并且是唯一在该频段内能获得高的品质因数的器件。本文简要介绍了 SAWR 基本构成及作者在 ST 石英基片上研制的两种 SAWR。参3     

微波和毫米波铁氧体移相器

本文详细论述了微波频段普遍使用的三种铁氧体移相器(即双环铁氧体移相器、双模铁氧体移相器和旋转场铁氧体移相器)的性能,讨论了由铁氧体饱和磁化强度值所确定的这三种器件的使用频率。     

雷达吸收材料使用六方晶铁氧体的技术 第二部份：减小高频和超高频金属线天线的雷达截面

在微波频段,金属线天线涂以六方晶铁氧体涂料会减小后向散射雷达截面,在高频和超高频通信频带内也不会引起辐射效率的显著变化。本文推导了在无限长圆柱导体的表面上涂以多层六方晶铁氧体涂料的后向散射雷达截面,其结果加以修正可以用来估算有限长单极天线的后向散射雷达截面。给出多层涂复的计算结果是为了说明在一定的涂层厚度下,在微波频段内后向散射特性所能得到的改善。根据计算结果可见这种技术最适用于各层涂料的特性及其几何参量均具有锥削分布的情况,同时要在所需的频段內将铁磁材料的谐振频率参差配置。最后,在微波频段(对入射波为TM和TE极化而言),这个原理通过对超高频铁氧体涂复天线减小后向散射的测量和对该天线在超高频段的辐射特性的测量而得以证实。     

雷达的未来发展机遇

自第二次世界大战初期问世以来，雷达在军事防空和其它军事行动中起到了积极的作用。由于二战的需要，雷达技术飞速进步，并得到广泛应用，而且这种技术的进步一直延续至今。1939年，第二次世界大战爆发时，大多数雷达工作在甚高频(VHF)频段(100～200MHz)。那时，甚高频属于无线电技     

VHF频段BP机干扰的形成及其抗干扰措施

本文在测量与分析甚高频（ＶＨＦ）通信频段受ＢＰ机台干扰原因的基础上,经过对干扰信号产生的机理分析,提出了抗ＢＰ机台干扰的措施和方法。     

M120高频机常见故障检修预防

Ｍ１２０高频机是一种高技术通信终端,它综合了双向高频机通信的最新技术,能在各种恶劣环境中保持有效和可靠的通信。它有甚高频(ＶＨＦ)和超高频(ＵＨＦ)两个频段:甚高频频段是１４６~１７４ＭＨｚ;超高频频段是     

镍掺杂W型铁氧体的制备及电磁性能研究

采用固相球磨法,制备了镍掺杂W型铁氧体Ba(Zn1-xNix)Fe16O27粉体。利用XRD及SEM分析了所制粉体的相组成及形貌,用微波网络分析仪对镍掺杂W型铁氧体粉体的微波电磁性能进行了研究。结果表明:1300℃时,生成了W型铁氧体相,形成了较完整的平面六角片状结构。在2～18GHz频段,随着Ni掺杂量的增加,W型铁氧体的ε'、μ'和μ"的值随之增大,在镍掺杂量达到最大时(x=1.0),磁损耗达到最大。     

雷达吸收材料使用六方晶铁氧体的技术 第一部分：宽带平面涂料

以前,在微波频段,由于缺乏导磁率大于“1”的材料,因而,难以设计微波频段薄的宽频带雷达吸收材料的涂料。一个可能解决的办法是利用六方晶铁氧体。这种六方晶铁氧体在窄频带内呈现的μ_1近似为“5”,这很有意义。本文涉及使用这种材料的方法,以便设计出薄的宽频带微波吸收材料。这里,要涉及到材料的分层,材料电参数的安排,和选择材料的几何尺寸,以便使入射波得到良好的匹配。通过对成品材料的测量,已证实了计算结果的准确性。测量技术和所用材料的详细情况在附录给出。在5—20GHz频段内,可使反射损耗大于10dB,而厚度又切实可用的一种平面吸收材料片已问世了。     

彩色电视机的预选电路

电视广播分两个波段，一个叫甚高频波段（VHF），另一个叫特高频波段（UHF）。国内目前还正在开发超高频波段（SHF）。我国将VHF波段又分为Ⅰ、Ⅱ频段，其中Ⅰ频段包括1—5频道；Ⅱ频段包括6～12频道；UHF波段也分两个频段Ⅳ和Ⅴ，其频道范围为13—57。与之相应的电视机便也要在一定的频段上工作，彩色电视机能够接收VHF及UHF两个波段的电视节目，所以它属于全频道产品。     

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.     

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 rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

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.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks