一种C波段大功率谐波滤波器的设计

介绍了在大功率要求下一种C波段谐波滤波器的设计方法,采用漏壁式低通滤波方式,结构上分为主波导和副波导阵。该滤波器通带内电压驻波比小,插入损耗低。该设计使得滤波器耐功率高,可靠性好,可适用于多种大功率侦察设备。     

一种基于协同仿真C频段大功率带通滤波器设计

针对接收机因发射机寄生输出引入干扰使系统无法正常工作的问题,需研制一种高功率带通滤波器,既要满足通带低损耗的传输又要对接收频带高的抑制度。滤波器传统设计方法包含大量理论计算和公式推导,整个设计过程非常繁琐。基于此问题,提出了一种场路协同设计大功率波导滤波器的方法,通过电路仿真软件Designer设计的滤波器得到带通滤波器的初值,再通过HFSS(High Frequency Structure)电磁仿真软件对初值进行优化仿真,最终完成了一种C频段高功率波导带通滤波器的设计。该大功率波导滤波器仿真结果很好地满足了设计目标,基于仿真结果,进行了小批量的加工。实测结果表明,该滤波器带内插损小于0.2 dB,驻波系数小于1.2,在5.1 GHz处阻带抑制度大于50 dB,整个滤波器的尺寸仅为240 mm×88.9 mm×63.5 mm。该大功率滤波器的实测结果与仿真结果有很好的吻合度,满足工程的设计要求。     

一类大功率微波滤波器的一个简化的设计方法

对于过渡波导节构成的一类大功率微波滤波器,我们建立了过渡节的等效电路,最后,根据此等效电路我们即可建立单节及多节由过渡波导节构成的大功率微波滤波器的分析和设计的一个简化方法。     

C波段大功率谐波滤波器设计

介绍一种C波段大功率谐波滤波器。该滤波器采用同轴传输线周期性结构实现谐波滤波特性，输入输出接口采用标准的BJ-48波导，以便于与发射机输出馈线系统的接口连接，整个滤波器的设计构思巧妙，结构紧凑，零件少，易于装配，不用调试，而且整个滤波器以完全空气介质实现，因而通带损耗小，有利于高功率传输。本文主要给出基本理论、设计思路、仿真和实验测试结果。     

基于双模谐振器的W波段波导带通滤波器

带通滤波器为现代毫米波系统中进行频率选择的重要器件,而波导滤波器因其低损耗、大功率容量、易加工等优点成为首选。为满足系统的小型化要求,设计了一种基于双模谐振器且具有准椭圆函数响应的W波段波导带通滤波器。该波导带通滤波器结构简单紧凑,由两个双模方形脊谐振腔组成,可获得2 个传输零点及四阶准椭圆函数响应。滤波器样品选取紫铜材质,采用CNC 技术加工制作。经矢量网络分析仪测试,该滤波器通带内插损低,达0.5 dB,3 dB 波束带宽为4.35 %(92.2 ~96.3 GHz),回波损耗优于20 dB,通带外存在两个非对称零点。在全W波段的测试结果与仿真数据高度吻合。     

一种X波段的大功率谐波吸收滤波器

设计了一种X频段基于双脊波导WRD650的大功率谐波吸收滤波器,采用双脊波导到单脊波导的渐变过渡结构,利用壁漏式结构,在脊波导宽边开孔,外接次波导谐波吸收腔;利用等效集总电路分析其设计原理,依据设计原理计算出模型初始尺寸,并在HFSS软件中建模优化。按照仿真结果加工实物,利用矢量网络分析仪对其散射参数进行测量。结果表明,该滤波器回波损耗均大于11 dB,通带插损均小于1 dB,阻带隔离均大于20 dB。     

一种新型小型化Ka波段波导带通滤波器的研制

设计了一种新型的小型化Ka波段波导带通滤波器。为了增加滤波器的带外抑制能力,在波导带通滤波器中设计插入了一个销钉。通过分析波导中销钉的等效电路,对加入销钉的滤波器进行了电磁场仿真设计。仿真结果表明,插入销钉的滤波器在高端引入了一个传输零点。按照仿真结果设计制作了波导带通滤波器,测试结果表明,该结构在保证性能指标的基础上有效的减小了波导滤波器的尺寸。该滤波器具有插入损耗低、零点位置调配灵活、体积小等优点。     

介质加载大功率消失模滤波器的设计

针对腔体滤波器低气压下容易发生大功率击穿的难题,提出了一种局部加载介质的消失模结构,可以有效避免滤波器低气压放电。设计了一款X波段宽带大功率消失模滤波器,利用三维仿真工具进行仿真优化,并根据电磁场仿真结果计算低气压击穿功率阈值。对制作的样品进行了性能测试,测试特性曲线与仿真曲线吻合;同时,进行了低气压功率试验,样品通过了300 W低气压(1 000~1 mbar)功率试验。通过该方法设计制作的消失模波导滤波器具有宽带匹配性能良好、Q值高、损耗小和低气压击穿功率阈值高等特点。     

基于基片集成波导的硅微机械滤波器

基片集成波导(SIW)结构是在低损耗的基片上利用金属孔构成的波导结构,具有高品质因数、大功率特性和易于集成的优点,是最近微波电路研究的热点技术.滤波器是微波毫米波电路中最常用的器件,使用SIW可以实现高性能滤波器且保持体积小的优点.     

小型化窄边单脊波导滤波器设计

通过仿真分析了窄边单脊波导的基本特性,采用所加脊不贯穿整个波导纵向的形式作为单脊波导谐振器,组成直接耦合的切比雪夫带通滤波器,同时输入、输出采用了同轴馈电的方式,与标准波导滤波器相比,可大幅度减小滤波器的体积。最后得到的测试结果表明,该结构能很好地实现波导滤波器的小型化设计。     

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.     

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.     

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.     

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