声表面波脉的冲编码调制振荡器

论述了一种直接式声表面波脉冲编码调制振荡器的工作原理及设计方法。实际制作了工作频率为３９４ＭＨｚ、调制频偏大于２００ｋＨｚ、调制信号码速率大于４００ｋｂｉｔ／ｓ输出率大于５０ｍＷ、温度稳定性优于±５０×１０＾－６（－２０－＋６０℃）的性能优良的声表面波脉冲编码调振振荡器。     

声表面波调频振荡器

论述了声表面波调频振荡器的原理及设计方法，探讨了有关电路，并制作了中心频率３８０．８ＭＨｚ的声表面波调频振荡器。当调制信号频率区ＤＣ至８００ｋＨｚ变化，幅值为２．５Ｖ时，调频频偏大于５５０ｋＨｚ；当调制信号频率小于或等于２００ｋＨｚ，幅值为１．０Ｖ时，调频非线性失真小于３．５％。振荡器经过温度补偿，温度稳定性优于±１５０ｐｐｍ（－４０℃～＋５０℃）。     

用于脉冲压缩雷达的声表面波部件

介绍一种用于脉冲压缩雷达的声表面波部件。它包含了声表面波脉压线、声表面波振荡器和重要的电子线路。该部件产生一种脉冲展宽信号，其工作频率为９６０ＭＨｚ，信号带宽为６ＭＨｚ，色散时间为１０μｓ，杂波电平≤－５０ｄＢｃ。专门设置的９００ＭＨｚ本振输出电平≥７ｄＢｍ，杂散电平≤－８０ｄＢｃ     

宽频偏声表面波压控振荡器研究

介绍宽频偏声表面波压控振荡器的实验研究。这种声表面波压控振荡器的工作频率为１８．３～１９．２ＭＨｚ，分四个频段进行数字信号控制，每一频段的压控频偏均大于３００ｋＨｚ，单边带相位噪声优于－１００ｄＢｃ／Ｈｚ／１ｋＨｚ，平均压控灵敏度大于５０ｋＨｚ／Ｖ。     

脉位调制式声表面波射频标签的回波时延估计

脉冲位置调制式声表面波(SAW)标签利用较少的反射脉冲实现高效编码,正逐渐取代开关键控编码成为声表面波射频标签的主流编码方式.反射回波之间的时延估计精度成为该方式编码容量和解码的核心.该文提出了一种利用计算回波包络二次相关的高精度估计回波脉冲时延的方法.研究了插值算法对相关峰值估计的影响.通过实际声表面波标签回波信号的实际测试和对照实验,证实了该方法的有效性.     

-50dB旁瓣脉冲压缩信号处理新方法

本文提出一种设计低旁瓣脉冲压缩信号处理的新方法,由希望的压缩脉冲波形来设计脉冲压缩系统的冲击响应。理论设计了时间分辨率优于海明加权,旁瓣电平－５０ｄＢ的脉冲压缩系统。实验用声表面波（ＳＡＷ）延迟实现．理论计算（－５０ｄＢ旁瓣）与实验测量结果相一致。     

声表面波振荡器应用飘红

声表面波振荡器是20世纪60年代末、70年初出现的一种新型振荡器。自Maines、Grabb和Lewis等人报道了这种振荡器之后,在这40年的时间内,人们对声表面波振荡器的研究取得了很大的进展,不仅阐明了它的原理、类型,而且研究了声表面波振荡器的性能及影响性能的各种因素,促进了制造工艺技术     

影响声表面波振荡器的频率稳定性因素分析

本文阐述了影响声表面波振荡器频率稳定性的主要因素;探讨了改善声表面波振荡器频率稳定性的方法。     

声表面波振荡器及其应用

本文介绍声表面波振荡器的工作原理、性能,以及影响性能的各种主要因素.还介绍了声表面波振荡器的各种应用.     

Y－78°X－90°LiNbO_3基片温度特性的理论研究

给出了Ｙ－７８°Ｘ－９０°ＬｉＮｂＯ＿３基片温度特性的一些研究结果，在材料温度系数只取到一阶时，随着温度的增大，自由化和金属化表面的声表面波速度线性减小，而ＴＣＤ值线性增大，且与实测值相一致。     

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