复口径Kirchhoff褶积公式和孔径辐射的复射线束仿真

本文基于解析延拓的概念,由实口径的Kirchhoff褶积公式导出了复口径的Kirchhoff褶积公式。理论分析和数值计算表明,利用复口径Kirchhoff褶积公式可以实现对孔径辐射场的复射线束仿真,从而为进一步研究孔径辐射场在复杂媒质中的传播提供了一种新方法。     

复口径Kirchhoff褶积公式和孔径辐射的复射线束仿真

本文基于解析延拓的概念，由实口径的ｋｉｒｃｈｈｏｆｆ褶积公式导出了复口径的Ｋｉｒｃｈｈｏｆｆ褶积公式。理论分析和数值计算表明，利用复口径Ｋｉｒｃｈｈｏｆｆ褶积公式可以实现对孔径辐射场的复射线仿真，从而为进一步研究孔径辐射场在复杂煤质中的传播提供了一种新方法。     

用复射线展开法计算目标散射场的误差特性分析

复射线展开法是计算目标散射场的一种简捷的方法,其可靠性有赖于对误差特性的系统研究。本文以平面波谱积分为散射场计算的参考标准,以L2空间中由范数定义的距离作为复射线展开法计算结果的误差,从而得到了复射线展开法在目标散射场计算中的误差特性,找到了减小误差的方法并给出这一方法的适用范围。     

分析大口径凹形结构散射的一种混合射线方法

在大口径凹形结构散射的特点及有关分析方法的基础上,提出了一类基于复射线方法和几何绕射方法的分析处理大口径凹形结构散射的混合射线方法,即用复射线法计算反射场,以几体绕射法来计算边缘绕射场。基于所设计的便于工程上实现的计算流程,有关分析及相关结果说明了这一方法的可行性和可靠性。     

三维高斯波束跟踪传播损耗预测改进模型

针对传统射线跟踪法需要考虑绕射并涉及接收球处理,从而算法复杂、计算量大等缺点,提出了一种基于三维高斯波束跟踪和二维网格加速的电波传播预测模型。该模型通过Gabor分解法将任意口径场分布展开为高斯型口径分布,直接实现了波场积分的离散化处理;高斯波束场采用复射线场模拟,并借助几何光学法加以复延拓,可处理反射、绕射和折射等复杂问题。相比传统射线跟踪法,本文模型无需考虑接收球处理和绕射,具有数学推导简单以及计算量小等优点。数值仿真结果表明,新模型预测精度与传统射线跟踪法基本相当,但预测效率可提高数十倍。     

用复射线展开法计算目标散射场的误差特性分析

复射线展开法是计算目标散射场的一种简捷的方法，其可靠性有赖于对误差特性的系统研究，本文以平面波谱积分为散射计算的参考标准，以Ｌ＾２空间中由范数定义的距离作为复射线展开法计算结果的误差，从而得到了复射展开法在目标散射场计算中的误差特性，找到了减误差的方法并给出这一方法的适应范围。     

基于反射阵技术的平面型副反射面设计方法

提出一种基于反射阵技术的平面型副反射面设计方法。根据双反射面天线的焦点变换关系,得到了平面型副反射面的相位补偿规律。采用开口环形单元设计了一种平面型副反射面,将初级馈源±20°的入射波束转化为照射角为±35°的散射波束。仿真对比了散射波束照射天线主面的口径效率。采用所设计的平面型副反射面,天线口径效率达到61.14%,与金属副面64.02%的口径效率相差无几。平面型副反射面采用印制板工艺制作,具有精度高和成本低的技术优势。     

复射线理论应用于天线一体化设计

分析自由空间天线辐射特性的方法已十分成熟,如口径场积分法、平面波谱积分法等,它们大都是行之有效的,但要求对天线及天线罩进行一体化分析时,现有的经典方法往往不能迅速而准确地给出解答,如果用复射线理论这一新方法则可以对某些问题圆满地给出结果.根据复射线理论,利用复源点远场具有的高斯波束特性,无论是在远区或是近轴区域内,复源点场和高斯函数有很接近的相同分布,理论上论证了对于具有高斯波束分布的口径场可以用复源点场来近似模拟.     

腔体结构电磁散射分析新方法

本文提出一种综合了复射线和几何光学射线法优点的腔体结构电磁散射分析方法－高斯射线管方法。讨论了单位平面波的高斯射线管模拟，以及高斯射线管在曲界面上的反射问题。给出了用高斯射线管计算腔体结构散射的典型算例。     

口径/谱域积分-表面积分法的研究

 通过分析口径积分、平面波谱理论关于天线近场计算的特点,获得一种混合的天线近场计算方法.结合表面积分技术,提出了口径/谱域积分-表面积分法,用于三维天线-罩系统电性能数值仿真.该方法吸取了口径积分和平面波谱理论的优点,对于天线近场的分析更为精确、实用.以弹载天线罩为仿真实例,结果表明,与口径积分-表面积分法和平面波谱-表面积分法相比,口径/谱域积分-表面积分法的计算结果与实验结果更为吻合,证明了该算法具有更高的精确度.     

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.     

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