一种基于子空间分解的IIR信道盲辨识算法

本文证明了对IIR信道输出进行过采样（采样率是输入码率的整数倍）可以转化成单输入多输出的多信道模型，并且不同的信道有相同的AR系数。基于这一特性本文提出一种基于子空间分解的信道参数盲辨识方法，即不同信道的MA系数可以输出信号的噪声子空间唯一确定，而AR系数则可以通过求解YW方程得到。     

分布式MIMO雷达的目标定位

针对多输入多输出雷达系统，研究了目标定位问题，并提出基于双基测距的分布式多输入多输出(Multiple-Input Multiple-Output, MIMO)雷达的目标定位算法。首先，通过引入多余参数和这些参数与未知目标定位的关系，将目标定位问题转化为约束二次规划(Quadratically Constrained Quadratic Programming, QCQP)问题，然后，考虑到QCQP问题是非凸和NP-Hard，再将每个非凸约束近似为线性约束，最终QCQP问题就转化为线性约束二次规划(Linearly Constrained Quadratic Programming, LCQP)问题。最后，利用迭代约束权重最小二乘(Iterative Constrained Weighted Least Square, ICWLS)算法求解LCQP问题。实验数据表明，提出的ICWLS算法能够收敛于一个最优值。     

交叉耦合微波滤波器输入/输出耦合系数抽取方法

交叉耦合微波滤波器可利用输入/输出耦合(即源与负载的耦合)构成交叉耦合以达到优化结构和减小体积的目的.首先基于波导缝隙耦合等效电路模型得到了S参数描述的输入/输出耦合系数;其次以X波段滤波器为例,使用HFSS软件抽取了输入/输出耦合结构的耦合系数,并根据目标耦合系数确定了其输入/输出波导耦合结构参数,从而将抽象的耦合矩阵转化成实际滤波器的结构尺寸;最后对比仿真结果与计算曲线验证了所提出方法的可行性.     

一种基于子空间分解的IIR信道盲辩识算法

本文证明了对IIR信道输出进行过采样 (采样率是输入码率的整数倍 )可以转化成单输入多输出的多信道模型 ,并且不同的信道有相同的AR系数 .基于这一特性本文提出一种基于子空间分解的信道参数盲辩识方法 ,即不同信道的MA系数可以由输出信号的噪声子空间唯一确定 ,而AR系数则可以通过求解YW方程得到     

空时编码多载波码分多址MIMO系统下行频率选择性信道盲估计

基于子空间方法的无线信道盲估计由于其算法的固有特性,使得估计结果与实际信道之间存在一个不确定复系数,无法得到无线信道的精确估计。在利用子空间分解方法对空时编码多输入多输出MC-CDMA系统下行频率选择性信道盲估计的基础上,利用发射符号的有限码集特性,将单载波系统下的模糊复系数盲辨识方法推广到多载波多输入多输出系统,从而得到信道的精确估计。Monte-Carlo仿真表明,在信噪比较低的情况下,本方法的信道估计误差仍然较小。     

如何确定干线放大器的实际输出和输入电平

如何确定干线放大器的实际输出和输入电平田祖德（湖南省凤凰县有线电视台）随着有线电视系统的扩大，干线传输距离不断增加，线路上需要串接好多台放大器。因此，每台宽带放大器最大输出电平必须由放大器串接后，到系统终端的非线失真系数满足系统终端互调与交扰调制失真...     

具有输入饱和的纯反馈系统有限时间跟踪控制

针对具有输入饱和及输出约束的非线性纯反馈系统,提出了有限时间自适应神经跟踪控制方法.利用有限时间控制理论、Barrier Lyapunov函数以及径向基函数(RBF)神经网络设计出新颖的虚拟和实际输入信号,解决了具有输入饱和及输出约束的非线性纯反馈系统的有限时间控制问题,同时,确保系统在满足输入饱和及输出约束的条件下,系统的输出在有限时间内跟踪上参考信号,并且系统的跟踪误差在有限时间内被限制在原点的小邻域内.最后,仿真实验阐明了所设计控制器的有效性.     

瑞利衰落时MIMO无线通信系统分集性能分析

针对多输入多输出（MIMO）无线通信系统提高系统性能的同时增加了系统的复杂度，提出了基于最大特征值传输的分集解决方案，在天线数量一定的情况下最大可能的提高系统的分集增益。对单输入多输出和多输入多输出的情况进行了数学分析，推导出了系统性能的变化范围，并且对分析的结果进行了数值仿真。     

递归滤波用于目标增强的性能分析

时域递归滤波器由于其结构简单,被广泛用于序列图像中的降噪和目标增强处理。通过对递归滤波器输入、输出信号信噪改善比进行理论分析,得出迭代系数、目标持续长度等因素对于信噪改善比的影响关系;指出了递归滤波器设计过程中确定迭代系数时应注意的问题,并给出递归滤波用于目标增强时最佳迭代系数的确定方法。     

MIMO-OFDM时变信道修正KALMAN跟踪

研究了在多输入多输出正交频分复用系统(MIMO-OFDM)中，时变信道的跟踪。在实际的通信系统中，接收端并不知道基站与移动台的相对运动速度，就不能得知时变信道多普勒频移的值，也就不知道时变信道构成的状态矢量的转移系数。普通的KALMAN跟踪算法，只能在假定的状态转移系数下对时变信道进行跟踪。本文提出的修正KALMAN滤波，能够同时跟踪时变信道以及时变信道构成的状态矢量的转移系数。     

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.     

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