基于Ba_xSr_(1-x)TiO_3薄膜电容的L波段可调滤波器

在蓝宝石基片上使用Ba_xSr_(1-x)TiO_3(BST)铁电薄膜电容作为可调元件制作出一种五阶梳状线可调带通滤波器。通过对BST平行板电容的材料特性(介电常数、损耗和可调率)的提取,其中40 V偏压下的可调率为43.1%,将这些特性运用于可调滤波器的制作。初步的实验结果分析表明,在20V直流偏置电压作用下,滤波器的中心频率从1.19GHz变化到1.31GHz(可调率为10.1%),带内插入损耗为13.5~13.7dB,回波损耗低于12dB。     

音箱研讨(三)——扬声器低频参数的测试和计算

图5测试Bl的原理图(a)测试振膜移位的电路直流电源 指示灯小金属片探头(可调距离)(b)使振膜复位的电路扬声器 可调电源 电A流表4其他参数的测试和计算[5](1)CMS为扬声器的力顺(单位:m/N),用下式求得CMS=14!2×f2s×MMS(21)(2)CAS为扬声器的声顺(单位:m3/N),用下式求得CAS=CMS×     

可调谐微机电电感(英文)

射频可调谐微电感在当前发挥着重要作用,它能满足高性能紧凑型器件设计的要求。对于器件设计者来说,可调电感能调谐电感量并能保证较高或适当的品质因素(Q值),这种能力在可调谐系统中比可调电容更有优势,因为可调电容可靠性较低并且大量占用基片面积。可调电感能节省芯片面积,它为将来便携式通讯系统所需的大范围可调谐系统提供一个优选的方案。因此,从器件角度对可调电感进行综述。根据可调电感的调谐机制,可调电感可分为四大类:离散型、金属屏蔽型、磁芯调谐型和线圈耦合型。对文献报道的可调电感进行概括,讨论这些可调电感优点和缺点,同时也介绍了这些可调电感的制备工艺、结果比较和其应用等。     

0-150V可调直流稳压电源

输出电压超过50V的可调直流稳压电源目前尚不多见。在某些需要所谓“中压”电源的场合,往往只能利用多路低压电源串联供电,既不经济又不方便,而且容易引起故障。本文介绍的0—150V可调直流稳压电源(以下简称可调电源),便是根据这类需要而设计的,适合于实验室内使用,也可作为某些专用仪器设备的自备电源。     

声控喷泉

在特定的时间内(0.5～10s可调),对该声控喷泉连续发声三次后,喷泉才会喷出4m多高的水雾,持续一定的时间后(1～10分钟可调),喷泉自动停止。工作原理:电路见附图所示。声控电路和延时电路由集成块SK—4完成,W_1调节延时时间;执行部分可用晶本管作开关,动作可靠、灵敏。当话筒在设定的时     

Maxim MAX17523A 4.2V-36V 1A电流限制器解决方案

<正>Maxim公司的MAX17523/MAX17523A是业界最小的和强健的集成系统保护解决方案,可调过压和过流保护器件非常适合正和负输入电压故障高达±40V的系统保护,具有190mΩ(典型值) RON集成的FET. MAX17523的可调过压范围在6V和36V之间,而可调欠压范围在4.4V和24V之间.过压锁住(OVLO)和欠压锁住(UVLO)阈值是33V(典型值),而目前的内部UVLO阈值为19V(典型值).     

DDS信号源的FPGA实现

采用直接数字频率合成技术(DDS),通过数字控制相位信号的增量在FPGA中实现频率可调的信号发生器,所产生的信号不仅幅度频率灵活可调,并具有频率分辨率高、切换速度快、相位噪声低等优点,因而该系统设计在相关的科研实践中具有重要意义.     

基于MATLAB的间歇反应釜系统识别、自适应控制与仿真

本文通过对反应釜的数学模型进行推导和简化,使用最小二乘法(LS),递推最小二乘算法(RLS),神经网络和系统识别工具箱分别对系统进行辨识,同时使用可调增益自适应控制算法对温度进行自适应控制,结合模型仿真结果分析表明可用于实际生产。     

高手接招

我有一台熊猫17英寸黑白电视机,开机半个小时左右,出现场抖动,同时出现颜色变黑,关机一段时间后再开机,十来分钟又会出现抖动。检查发现行输出管集电极电压只有20V。把机板上的可调电阻换上后无效,调电源取样放大管的基极可调电阻(470Ω),输出     

一种新偏压结构的BST电容梳状滤波器设计

介绍了一种五阶可调抽头式梳状线滤波器,设计采用共面方式接地,使用Ba0.6Sr0.4TiO3 (BST)铁电薄膜平板电容作为可调部件,并分析了平板电容结构的影响.针对梳状电调滤波器需单阶加压和外接大电阻繁琐的情况,提出利用集成在衬底上的大容量BST电容作为隔离电容,将各阶谐振器的偏压线互连来简化加压过程.运用高频电磁仿真软件HFSS进行验证,设计出的滤波器中心频率可调范围为842～960 MHz(14％),3 dB带宽为9％～10％.     

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.     

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.     

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.     

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.     

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