一种QFN24封装的适用于0.5GHz-3GHz应用的4X2矩阵开关

This paper presents a 4×2 switching matrix implemented in the Win 0.5 m Ga As pseudomorphic high electron mobility transistor process, it covers the 0.5–3 GHz frequency range. The switch matrix is composed of 4 SPDT switch whose two output ports can simultaneously select the input port and a 4 to 8 bit digital decoder,both the radio frequency(RF) part and the digital part are integrated into one single chip. The chip is packaged in a low cost QFN24 plastic package. On chip shunt, capacitors at the input ports are taken to compensate for the bonding wire inductance effect. The designed switch matrix shows a good measured performance: the insertion loss is less than 5.5 d B, the isolation is no worse than 30 d B, the return loss of input ports and output ports is better than –10 d B, the input 1 d B compression point is better than 25.6 d Bm, and the OIP3 is better than 37 d Bm. The chip size of the switch matrix is only 1.45×1.45 mm2.     

基于极点展开法无芯片电子标签的识别与传感

利用极点展法得到的极点与留数,可对无芯片电子标签进行识别与传感.由极点与标签结构成对应关系,利用衰减因子与谐振频率可对标签结构的基本属性进行识别,还可以进一步地感知标签结构的弯曲变形程度;利用留数所含有的信息,可以感知标签结构相对入射波或观测点的空间角度方位信息.通过理论仿真分析,极点与留数不仅可用来识别标签,还可以感知标签结构的其它特性的功能.     

First order Feynman–Kac formula

We study the parabolic integral kernel for the weighted Laplacian with a potential. For manifolds with a pole we deduce formulas and estimates for the derivatives of the Feynman–Kac kernels and their logarithms, these are in terms of a ‘Gaussian’ term and the semi-classical bridge.     

一种高速高增益CMOS运算放大器的设计

设计了一种应用于采样保持电路中高速高增益运算放大器。该运放采用全差分增益提高型共源共栅结构。在输入信号通路上加入适当的补偿电容,消除了零极点对对运放建立时间的影响,同时对主运放的次极点进行了优化,改进了相位裕度。采用0.35μmCMOS工艺仿真,结果表明,运放的开环直流增益达到106dB,单位带宽为831MHz（负载电容8pF）,相位裕度为60.5°,压摆率为586V/μs,满足12位50MS/s流水线ADC中采样保持电路性能要求。     

一种高频带通LC滤波器的设计方法

以带通滤波器的基本电路为例,对电路中通常存在的缺陷和可能造成的问题进行了分析,着重介绍了一种采用网络变换对电路进行优化并合理利用极点放置技术的经济、高效设计方法,并通过试验证明了采用该电路构造滤波器的可行性和优点。     

二元对角向量值有理插值的算法

首先提出了二元对角向量值有理插值问题,它包括主对角和副对角两种向量值有理插值,并分别给出了主对角线和副对角线上向量值有理插值的两种算法,即直接求系数bi,j的算法和基于Samelson广义逆所定义的特殊初等变换的矩阵算法.然后构造了在预给极点情况下求主对角线和副对角线上向量值有理插值的矩阵算法.最后给出多个数值例子说明上述算法的有效性.     

Low rank update of singular values

The notion of a low rank update arises in many important applications. This paper deals with the inverse problem of updating a rectangular matrix by additive low rank matrices so as to reposition the associated singular values. The setting is analogous to the classical pole assignment problem where eigenvalues of a square matrix are relocated. Precise and easy-to-check necessary and sufficient conditions under which the problem is solvable are completely characterized, generalizing some traditional Weyl inequalities for singular values. The constructive proof makes it possible to compute such a solution numerically. A pseudo algorithm is outlined.

     

Applying numerical continuation to the parameter dependence of solutions of the Schrödinger equation

In molecular reactions at the microscopic level, the appearance of resonances has an important influence on the reactivity. It is important to predict when a bound state transitions into a resonance and how these transitions depend on various system parameters such as internuclear distances. The dynamics of such systems are described by the time-independent Schrödinger equation and the resonances are modeled by poles of the S-matrix.Using numerical continuation methods and bifurcation theory, techniques which find their roots in the study of dynamical systems, we are able to develop efficient and robust methods to study the transitions of bound states into resonances. By applying Keller’s Pseudo-Arclength continuation, we can minimize the numerical complexity of our algorithm. As continuation methods generally assume smooth and well-behaving functions and the S-matrix is neither, special care has been taken to ensure accurate results.We have successfully applied our approach in a number of model problems involving the radial Schrödinger equation.     

引导混沌运动到周期运动的自适应控制策略

提出一种自适应控制策略，对控制参数作线性反馈将非线性动力系统由混沌运动引导到指定的周期运动．所解决的关键问题是将反馈控制强度的确定转化为扩维相空间中的极点配置问题．给出了将该策略用于控制Ｌｏｇｉｓｔｉｃ映射和受迫Ｄｕｆｉｎｇ振子的仿真．