bluuebunny/crossref_metadata_2025_split huggingface dataset:
Higher derivative network sensitivities using adjoint network
Authors: Seth A. K. , Roe P. H. 
Published: June 2007

AbstractHigher derivative sensitivity coefficients for a lumped linear time‐invariant networks are derived by an extension of the method used by Richards to calculate second derivative sensitivity coefficients. A computer algorithm to generate these coefficients efficiently is provided together with array space and the number of operations required at each stage. Extensions of the above approach for networks containing distributed and nonlinear elements are also discussed. Finally, time domain sensitivity results are derived and the corresponding changes in the computer algorithm indicated.
Applications of the discrete green's function concept in circuit theory
Authors: Gruner L. 
Published: June 2007

AbstractIt is shown that the analysis of a network comprising passive, active, reciprocal, nonreciprocal, lumped or distributed elements and excited by voltage and current sources distributed throughout the network can be very effectively undertaken with the aid of the discrete Green's function concept if the network may be represented as a chain of sub‐networks having known two‐port parameters and if independent sources are only present at ports joining these sub‐networks.The procedure offers computational advantages when the number of sub‐networks is large and moreover, it may be applied to the solution of other problems which are described by a large system of linear equations, when the coefficients form a band matrix.
A synthesis method for power network extension
Authors: Szendy Károly 
Published: June 2007

AbstractIn this paper the synthesis problem of power‐network extensions will be studied under the assumption that the loads are deterministic. The extended network satisfying conditions on the branch voltage limits will be optimized by the minimization of the network ‘first‐cost’. Useful notions such as network extension impedance and extension coefficient matrices will be introduced to describe the effect of network extensions. Two optimization methods will be presented. In the first one the cost function is linear and the constraints appear in the form of simple fractions. In the second method the cost function is assumed to be quadratic but the constraints are linear. In the latter case the extensible branches have to form a tree. It will be shown that sequential unconstrained optimization techniques can be applied in both cases.
Modeling of coupled multiconductor microstrip‐like transmission lines
Authors: Bálint L. 
Published: June 2007

AbstractCircuit models of multiconductor, longitudinally homogeneous guides having cross‐section of arbitrary geometry and filled with several different dielectric materials are investigated in the framework of the TEM and quasi‐static approach.The existence of uncoupled and orthogonal TEM modes is established providing a good approximation for multi‐conductor low‐loss lines having inhomogeneous dielectric filling. Utilizing these modes the lossy Z and Y matrices are derived. The circuit models can be used for frequency‐domain analysis of lumped‐distributed circuits.
The allowed varactor parameter tolerances for the electrical tunability of two microstrip parametric amplifiers
Authors: Sirkeinen Y. K. 
Published: June 2007

AbstractThe variations in varactor parameters which can be compensated by the electrical re‐tuning of two specific amplifiers have been studied using a digital computer. The designs of two different microstrip parametric amplifiers were at first optimized with respect to the bandwidth. Then after changing the varactor parameters, pumping and biasing conditions were optimized in order to attain maximum flat gain bandwidth within certain acceptable limits for gain and frequency. The results show that considerable variations can be compensated electrically.
Fourier coefficient design of stepped impedance transmission line networks
Authors: Rhodes J. D. 
Published: June 2007

AbstractThe conventional method of designing stepped impedance transmission line networks from gain functions requires the use of a factorization process to obtain a passive input impedance, and then the application of Richards Theorem to determine the element values. A new technique is presented based upon the determination of the Fourier coefficients of the return loss function from which the element values may be obtained immediately for the minimum phase reflection coefficient without any factorization process or synthesis procedure. It is believed that this new technique may be extended directly to the design of mixed lumped‐distributed transmission line networks whereas the conventional approach may not.
Networks containing periodically operated switches: A state space approach
Authors: Orfei R. , Pallottino G. V. 
Published: June 2007

AbstractA state space analysis is given of the networks containing periodically operated switches, by using a new approach based on the concept of time constant multiplication rather than on the conventional concept of resistance multiplication.The transfer function of two‐port networks containing P.O.S. is derived from a state model that does not require a detailed topological analysis of the network.The number and the location of the switches is discussed with particular reference to the problem of their minimization.Experimental results are given by illustrating an application of variable filters to the realization of a spaceborne spectrum analyzer.
A method of graphical approximation in synthesis of rc distributed networks
Authors: Řiazek Stanislav 
Published: June 2007

AbstractThe approximation problem in synthesis of RC distributed networks is discussed. The synthesis methods based on transcendental frequency transformations are considered. A method of graphical approximation of a required network function magnitude is proposed. The modified frequency is introduced to ensure asymptotic behaviour of the logarithmic plots and the relevant design‐charts are presented. They enable us to find out the locations of zeros of normalized factors from the prescribed values of the magnitude and frequency. A method of two‐step analytical approximation is also included. The proposed methods are very useful for the preliminary approximation that saves time for further numerical procedures by a computer. The methods presented are illustrated by an example.
Generation and classification of single amplifier filters
Authors: Sedra Adel S. 
Published: June 2007

AbstractA unified approach is presented for generating configurations for circuits containing one operational amplifier together with RC elements and capable of realizing a general second‐order voltage transfer function. Systematic application of the generation procedure leads to various single amplifier biquads with the known circuits, as well as some new ones, obtained as special cases. The insight gained from the generalized approach as well as the results of a general sensitivity analysis (including the effects of the amplifier limited bandwidth) offer a method for categorizing and classifying single amplifier filters. The different filter classes are illustrated and compared with the aid of extensive design tables. General equations for the effect of the amplifier limited bandwidth are also given.
Infinite networks of positive operators
Authors: Zemanian A. H. 
Published: June 2007

AbstractInfinite resistive networks have recently been analyzed by H. Flanders. The present work is an extension of Flanders results in three directions:

It analyzes the more general case where the resistances in the network are positive bounded linear operators on a Hilbert space H and the currents and voltages are members of H.
An infinite number of sources is now allowed.
The network is permitted to have finite loops of doubly infinite paths consisting entirely of short circuits.
Conditions are developed under which existence and uniqueness theorems for the set of branch currents can be stated.These conditions include the requirement that all branch resistances be either zero or invertible. The situation where some or all of the resistances have nontrivial null spaces is also considered. In those cases where the branch currents need not be unique for a given set of sources, the difference between two possible current distributions can be characterized as a current distribution that produces zero voltage drops in all branches. An application to time‐varying resistive networks containing switches is also given.
Low‐pass filters with maximally flat magnitude beyond the origin and arbitrary transmission zeros
Authors: Rabrenović D. , Jovanović V. 
Published: June 2007

AbstractAn analytical procedure for generation of a special type of critical monotonic magnitude characteristic, having maximal flatness at a given frequency ω0 beyond the origin, with arbitrary transmission zeros, is presented. Compared with the known filters with maximally flat magnitude at the origin and the same transmission zeros, the new filters show distinct improvement in the cutoff performance.
Effect of resistive losses on superconductive multimode oscillators
Authors: Parmentier R. D. , Costabile G. 
Published: June 2007

AbstractArrays of negative resistance tunneling elements can support multimode, multistate oscillations and have been proposed for information processing applications. Published studies have analyzed nonresonant mode interactions by treating the nonlinear tunneling currents as small perturbations on the time‐average behaviour of a linear lossless array, but they have neglected the effects of linear resistive losses. For an array of superconductive tunnel junctions, these resistive losses, treated using the same perturbation formalism, are shown to give rise to mode combinations in which some modes have negative energies, leading to the conclusion that such mode combinations cannot exist physically. Order of magnitude quantitative estimates indicate that such mode limiting effects might well occur in practical arrays and suggest how the array geometry might be modified to minimize these effects.
A three‐terminal piecewise‐linear modelling approach to dc analysis of transistor circuits
Authors: Hajj I. N. , Roulston D. J. , Bryant P. R. 
Published: June 2007

AbstractThe simulation of electronic circuits by computer has become an important part of present‐day circuit analysis and design, especially in the area of integrated circuit design. One of the goals in computer simulation of integrated circuits is to have a program ‘package’ for which the input consists of chip fabrication data (mask dimensions, impurity profiles, material data such as carrier lifetimes) and the output displays the complete circuit response. This requires both an efficient modelling approach and a fast circuit analysis method.In this paper a simulation method is described which generates dc responses (in the form of operating points or transfer characteristics) of transistor circuits directly from physical parameter data. The basis of the method is a two‐dimensional piecewise‐linear approach to the dc modelling of bipolar transistors. The model is directly used in a piecewise‐linear circuit analysis program to simulate the dc response of a given circuit.
Synthesis of n‐port active rc networks with a minimum number of capacitors
Authors: Stamenković Borivoje B. 
Published: June 2007

AbstractA 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.
A note on passivity and losslessness
Authors: Levan N. 
Published: June 2007

AbstractThis note gives new necessary and sufficient conditions for a linear system to be passive or lossless. It will be shown that, by using the theory of operators on an indefinite J(t)‐Hilbert space, both the passivity and isometric conditions for an operator to be lossless can be combined into a single condition—namely an operator is lossless if and only if it is J(t)‐contractive.
High‐frequency limitations of rc‐active filters containing simulated‐l and fdnr elements
Authors: Bruton L. T. , Haase A. B. 
Published: June 2007

AbstractHigh quality RC‐active filters may be realized using inductance‐simulation or FDNR‐synthesis techniques where generalized immittance converters (GIC) are the basic active two ports of the synthesis. The deterioration of the magnitude transfer function |T(jω)| at high frequencies is determined in terms of the gain bandwidth products B of the operational amplifiers employed within the GIC's. The basis of the method is to extend Blostein's lossless LC‐twoport tolerance by determining the magnitude and phase errors of the simulated‐inductance or FDNR elements.
Current and voltage graphs of a composite graph
Authors: Fischer Hans Dieter 
Published: June 2007

AbstractFrom a given composite graph two graphs are derived, which can be interpreted as current and voltage graphs, respectively. It is shown that a complete tree of both graphs is a directed tree of the composite graph. Thus the generation of directed trees is reduced to the generation of complete trees. The matrix belonging to the composite graph is decomposed in the incidence matrices of the current and voltage graphs and in a diagonal matrix whose elements are given by the edge‐weights of the composite graph. The number of directed trees in a composite graph is determined using the incidence matrices of both graphs.
The inverse laplace transform of a function of the m‐derived filters
Authors: Chen Wai‐Kai 
Published: June 2007

AbstractThe inverse Laplace transformation of a transfer function of the m‐derived wave filters is presented. Using this result, the transient responses of a composite wave filter and a distributed amplifier using m‐derived filter sections are derived. They are shown to be expressible as sums of integrals involving generalized hypergeometric functions in the same way that the solutions for other wave filters involve Bessel functions.
On the realization of gyrators by nullors and resistors
Authors: Adams K. M. , Deprettere E. 
Published: June 2007

AbstractIt is proved that for the realization of a gyrator by nullors and resistors, at least two nullors and at least two resistors are needed. A generalization is the result that any n‐port network possessing both an impedance and an admittance matrix and consisting of nullors and resistors must contain at least n resistors.It is conjectured that a realization of a gyrator with only two nullors requires four resistors and a realization of a gyrator with only two resistors requires three nullors.
Realizable filters which give zero intersymbol interference in an fsk system
Authors: Tomlinson Martin 
Published: June 2007

AbstractFilter constraints are given which enable filters to be designed which give zero intersymbol interference at the output of the frequency discriminator in an FM system; these constraints are developed in the frequency domain which enables satisfactory noise bandwidths to be obtained. The results are not limited to a particular deviation ratio and are applicable to both continuous and discontinuous phase systems. Some examples are given including a practical IF filter design for a 4.8 K bit/sec, 250 kHz centre frequency, 0.8 deviation ratio system. The noise bandwidth of this filter is 5.72 kHz and it is shown that the minimum possible obtainable noise bandwidth is 4.63 kHz.
Synthesis of low‐pass double‐ladder operational amplifier network with prescribed pole sensitivities
Authors: Murthy N. , Aatre V. K. , Ramachandran V. 
Published: June 2007

AbstractThis paper discusses the realization of low‐pass filters having a pair of complex conjugate poles by a multiple feedback RC operational amplifier network. When the pole sensitivity with respect to the amplifier gain is prescribed, it is shown that the gain can be determined and then the synthesis proceeds in a way similar to the one with an infinite gain amplifier. This structure uses fewer passive elements as compared to Hakim's structure and the quadratic sensitivity index is closer to its theoretical minimum.
The equidistant linear phase polynomial for distributed and digital networks
Authors: Fahmy M. F. , Rhodes J. D. 
Published: June 2007

AbstractA closed form expression for the recurrence formula for the generation of polynomials whose phase interpolates to linear characteristics at equidistant frequencies is presented. This polynomial may be used directly in the design of both distributed and digital networks and, due to the recurrence formula, readily generated. Since the complete proof of this formula is extensive and not required for normal use of this polynomial, it has been outlined in an Appendix.
A memristive circuit model for p‐n junction diodes
Authors: Chua Leon O. , Tseng Chong‐Wei 
Published: June 2007

AbstractA new simple lumped circuit model for junction diodes is presented. The model contains only 4 elements; namely, 2 controlled current sources, a nonlinear capacitor, and a memristor. Each component bears a simple relationship with the physical operating mechanisms inside the diode. The model is shown capable of simulating realistically the diode's dynamic behaviours under reverse, forward, and sinusoidal operating modes. Both the storage time and the fall time of the diode can be accurately predicted. The model is also shown capable of mimicking various second order effects due to conductivity modulation. In particular, the model is shown to exhibit a predominantly capacitive incremental impedance under small forward bias and a predominantly inductive impedance under large forward bias. Moreover, it includes the standard two‐capacitor model as a special case.
High‐frequency comparison of gic‐simulated inductance circuits
Authors: Bruton L. T. , Lim J. T. 
Published: June 2007

AbstractIt is shown that there is a significant difference in the high‐frequency behaviour of two well‐known generalized immittance converter realizations of simulated inductance. One of the realizations yields a Q factor that is highly sensitive to mismatch of amplifier bandwidths whereas the alternative realization can be designed to give a Q factor that is highly insensitive to this mismatch.
Bipartite network associated with optimal pivoting problem
Authors: Shirakawa Isao , Kyan Seiki , Ozaki Hiroshi 
Published: June 2007

AbstractThe coefficient matrix of a fairly large system of equations is generally very sparse. Thus in the computer‐aided analysis of such a system of equations, of prime importance are the sparsity‐oriented solution and storage techniques. Motivated by this problem, in the present paper we first define a bipartite network associated with a given system of equations, and then discuss the problem of sparsity‐preserving pivot ordering with the use of the bipartite network.
On pole distribution in digital filters
Authors: Rahman M. H. , Fahmy M. M. 
Published: June 2007

AbstractDue to the discrete nature of the coefficients the poles and zeros of a digital filter transfer function cannot, in general, be realized exactly. This paper introduces a new concept ‘pole sparsity factor’ as a measure of the maximum possible pole deviation after tuning, for the case of second order circuits. A new second order circuit that exhibits lower pole sparsity factor compared to presently available circuits with the same number of multipliers is presented.
CASCADE SYNTHESIS OF MONOLITHIC CRYSTAL FILTFRS POSSESSING FINITE TRANSMISSION ZEROS
Authors: Dillon C. R. , Lind L. F. 
Published: June 2007

AbstractA simple method for the synthesis of bandpass or bandstop filters possessing finite transmission zeros as a cascade of shunted double‐resonator monolithic crystal filter (MCF) sections is given. The lowpass or highpass prototype transfer function is synthesized as a cascade of MCF prototype sections for which explicit expressions for the element values are given. Application of the narrow‐band lowpass to bandpass frequency transformation to the prototype network then yields a physically realizable filter with the desired bandpass or bandstop response. An example of the synthesis of a bandstop filter is given to illustrate the approach.
Optimized design of cascaded active RC bandpass filters
Authors: Novák Mirko , Hruby Jaroslav 
Published: June 2007

AbstractThe synthesis of RC active filters composed of a chain of standardized selective functional blocks (SSFB's) is discussed. The rules for the optimal or quasioptimal choice of the SSFB's in the chain which leads to an increase of dynamic ratio and noise suppression are given. The design procedure of the SSFB's having very accurate and temperature stable parameters is described.
An electronically tunable RC active filter
Authors: Swamy M. N. S. , Rao K. Sankara 
Published: June 2007

AbstractAn RC active filter with embedded FET switches is presented for the realization of a general second order filter. The filter consists of minimal number of capacitors, two differential input dual output operational amplifiers, fixed resistors and resistors connected as potential dividers. The network has low Q and ω0 sensitivities; further, the finite bandwidth of the operational amplifiers has negligible effect on the Q of the filter.The introduction of FET switches in the network results in frequency scaling and consequently, the possibility of electronically tuning it. In addition, by switching the FETs by pulses of very low duty cycle, it is possible to obtain subaudio filters using resistive and capacitive components of smaller values than required for a conventional filter. Experimental results pertaining to the band‐pass case are also included.
On the active rc realization of rational admittance matrices with prescribed ranges of passive RC element values
Authors: Stamenkovič Borivoje B. 
Published: June 2007

AbstractFollowing a review of methods for the synthesis of grounded multiterminal active RC networks when grounded finite‐gain voltage‐controlled voltage sources (VCVSs) serve as active elements a new result is presented. It is proved that an arbitrary short‐circuit admittance matrix can always be realized with prescribed ranges of passive RC element values.
Interdigital filters with a linear phase and a minimum attenuation in the passband
Authors: Garault Y. , Jarry P. 
Published: June 2007

AbstractThe purpose of this paper is to determine a new class of characteristic polynomials for interdigital filters with short‐circuited input lines. The corresponding transmission factor provides (n–2) zero derivatives of its group delay at the origin and the attenuation is nearly nullified in the passband.