Synthesis of n-port networks by a matrix-continuant

A general RC active network synthesis procedure for the realization of the multiport is proposed in this paper. The method is developed and based on using matrix-continuants and simple matrix manipulations. A numerical example of the realization is also given.     

Cascade decomposition of a passive 2n-port network

This paper deals with a cascade decomposition of a passive 2n-port network. after a basic discussion relative to complex- and unit-normalized scattering matrices, necessary and sufficient conditions are presented under which given lossless 2n-ports D₁ and D₂ are simultaneously extractable from the front- and back-ends of the passive 2n-port N, respectively, to leave a passive 2n-port remainder Ne. Based on these conditions, some relations between the individual and simultaneous extractability of D₁ and D₂ from N for both degenerate and non-degenerate remainders N_e are discussed. the results are presented in terms of scattering as well as impedance matrices and can be considered as an extension of those given in Reference 1.     

(n +p)-node realizability of Y-matrices of (n + 1)-node resistance n-port networks

Sufficient conditions are established for the (n +p)-node, p>2, realizability of Y-matrices of (n + 1)-node resistance n-port networks. It is shown that these conditions are a generalization of the previous known results for p = 2 and p =n.     

Representation of noise in a particular type of linear n-port network

A noisy linear N-port network that can be represented by a noise-free linear N-port network with voltage and current noise sources at the ports is considered. If the linear N-port network has a particular type of admittance matrix, it is possible to show that as many as N/2 when N is even and (N – 1)/2 when N is odd of the ports may be cleared of noise sources. The total number of unique representations of such a network is given for both the general case and for the case when a particular port or ports must be free of noise sources.     

Synthesis of n-port active rc networks with a minimum number of capacitors

A new and practical synthesis procedure is presented for the realization of an arbitrary n × n matrix of real rational functions of the complex frequency variable as the short-circuit admittance matrix of a transformerless active RC n-port network. The realization requires a theoretically minimum number of capacitors p, where p is the degree of the matrix, and no more than (n + p + 1) grounded finite-gain phase-inverting voltage-controlled voltage sources. All the capacitors and ports are grounded. The freedom implicit in the synthesis procedure allows the inclusion of constraints on the passive element values. Furthermore, in special cases the realization is achieved with a reduced number of conductances and voltage-controlled voltage sources. The synthesis procedure is simple to apply and can readily be implemented on a digital computer. Several examples are given.     

Double broadband matching and the problem of reciprocal reactance 2n-port cascade decomposition

Let N, N₁, N₂ and N₃ be prescribed reciprocal reactance 2n-ports. Then, under certain mild restrictions, this paper supplies answers to the following two related problems:. P₁. Find the necessary and sufficient conditions for the physical extractability of N₁ from the front-end of N. P₂. Given that N₂ and N₃ are individually physically extractable from the back and front-ends of N. respectively, find a set of sharp sufficient conditions for their simulations physical extractability from N. The criteria are formulated in terms of the associated scattering matrices and are reasonably simple to apply. Moreover, they also have a clear-cut network significance involving transmission zeros. to illustrate their use, a recent result for the design of non-degenerate double broadband-matching equalizers⁶ is generalized to a 2n-port setting in Theorem 2, corollary 2. Lastly, to round out the development, impedance versions of both Theorem 1 and Theorem 2, corollary 2, are presented in Section 2. This restatement is accomplished with the aid of a new Darlington 2n-port embedding for passive reciprocal n-ports that is phrased entirely in the language of impedance matrices.     

基于电桥的高精度电阻测量系统的设计与实现

针对现有的电阻测量仪器和设备对于电阻测量的精度不高以及价格昂贵的问题,设计了一款基于电桥的高精度电阻测量系统。系统采用电桥电路作为测量电路,利用STM32F103RBT6单片机作为控制核心,主要通过基准电压电路和A／D模块电路实现测量电阻数据的采集与模数转换,同时,为了实现对电阻的高精度测量,通过硬件去耦滤波和软件数字滤波及误差补偿2种方式共同减小了接触电阻、导线电阻以及其他各类噪声的影响。系统在测量电阻时可以通过液晶显示六位有效位数字,即精度可达到十万分之一,分辨率为1mΩ;它具备电阻测量的操作简单、数据采集稳定、灵敏度高和成本低廉等特点,可以对各类电阻包括精密电阻的阻值测量,并且适用于应用于实验、维修和工程开发等多种场合。     

高土壤电阻率地区变电站接地网长效降阻的实现

广州番禺110kV祈福变电站所处地域的土壤电阻率较高,地网电阻值高达1．3Ω。为使地网电阻达到国家标准,首次在国内采用了世界先进的接地系统辅助设计工具——CDEGS软件包对祈福变电站接地系统进行了可行性设计论证,并予以实施最终使地网电阻降到了0．2Ω以下,确保了设备的安全运行。在此基础上,更纵深考虑了如何使在高土壤电阻率地区的变电站设计和改造工作更加科学合理,为今后在探讨相关工作时提供一套较完整的可行性系统解决方案。     

一种基于LDPC矩阵的压缩感知测量矩阵的构造方法

在一些对采样数据速率有严格要求的实际应用中,对低采样率的压缩感知具有广泛需求。基于LDPC矩阵的特点,提出了一种类似托普利兹矩阵的压缩感知测量矩阵,所提出的测量矩阵构成方法易于实现。仿真结果表明,在低采样率的情况下,采用本文所提方法构造的测量矩阵不仅有着与常用稀疏测量矩阵相比更好的稀疏性,且将其用于图像压缩感知时可获得较好的图像重构质量。     

Generation of constituent matrices

A simple method is outlined for evaluating the residues in a partial fraction expansion when multiple roots are present. Its application along with Frame's algorithm leads to an efficient scheme for the generation of the constituent matrices when multiple eigenvalues are present.     

市内通信电缆绝缘电阻特殊要求的实现和措施

本文对市内通信电缆的各生产过程进行分析、研究和控制 ,从而提出了解决绝缘电阻特殊要求的方法 ,以及改进的措施。     

摄动矩阵的分解

参数不确定系统鲁棒控制的设计均基于摄动矩阵的分解。本文给出一种系统性的清晰的分解方法，将摄动矩阵分解为三个矩阵，分别描述矩阵中的不确定元素及其所在的行位置和列位置。分解的步骤与行的顺序一致，最后用一个例子来说明这种分解思想。     

On rlc network matrices

A generalization of the coefficient conditions which hold for an RLC network as well as of the paramount property obeyed by the matrix of a resistance network is derived. This result is a property of either the nodal or mesh matrices for either the admittances or impedances of a general RLC network. It states that if P is any principal minor or such a matrix and Q any other minor constructed from the same rows (columns) as P then P, P + Q, P–Q are rational functions of the complex frequency variable which, before cancellation of common factors, have only non-negative coefficients.     

A class of nonrealizable paramount matrices

Although paramountcy¹ is a necessary and sufficient condition for the realizability of a 3 by 3 matrix as either an open-circuit impedance matrix or a short-circuit admittance matrix of a resistive 3-port,² Weinberg's 4 by 4 example^3,5 shows that paramountcy, although necessary for open-circuit impedance realization, is not sufficient. Here we exhibit a class of 4 by 4 completely irreducible paramount matrices, including Weinberg's example, no member of which is realizable as an open-circuit impedance matrix. This is accomplished by examining those topological constraints inherited by a realizing network when algebraic conditions are imposed on the paramount matrix which the network realizes. Our development deals with an n-port network, for arbitrary n, and also provides new criteria guaranteeing nonrealizability of an irreducible¹ paramount matrix.     

Block-pivoted condensation on impedance matrices

Given an n-port of nullity q, the Z -matrix of which is to be sought, we first construct a primitive Z -matrix of order q, and then apply to it the pivotal condensations with respect to q–n unspecified ports, one at a time. The present note discusses the problem of decomposing a network into blocks and then of seeking a port structure so that any pair of unspecified ports taken from different blocks have no coupling in the primitive Z -matrix. This enables us to apply a block-pivoted condensation to the primitive Z -matrix.