bluuebunny/crossref_metadata_2025_split huggingface dataset:
An edge‐oriented adjacency list for undirected graphs
Authors: Chen L. K. , Ting B. S. , Sangiovanni‐Vincentelli A. 
Published: July 2007

AbstractA new data structure, called the Edge‐Oriented Adjacency List (EOAL), for representing undirected graphs is presented. It provides more information on the edges and requires less storage space than the conventional adjacency list. Furthermore, it is superior to the conventional adjacency list in both insertion and deletion operations.
Existence of hybrid matrices for active n‐ports encountered in the analysis of transistor networks
Authors: Nielsen Richard O. , Willson Alan N. 
Published: July 2007

AbstractIt is shown that hybrid matrices exist for certain types of active n‐ports constructed using resistors and controlled sources. Furthermore, it is shown that the existence of these hybrid matrices implies that a certain well‐known set of necessary and sufficient conditions, which guarantees the uniqueness of solutions to the nonlinear DC equations of transistor networks, can be simplified. Additional results are presented which show how the amount of computation required to verify these conditions can be reduced.
Parametric representation of brune functions
Authors: Fettweis Alfred 
Published: July 2007

AbstractIt is shown that a parametric representation for Brune functions can be given which, although being more complicated than for Foster functions, is simple enough to be of practical interest. This holds in particular if use is made of substantial simplifications obtainable by eliminating certain subclasses of Brune functions which are of no practical interest. Applications to broadband matching and switched networks are pointed out.
Statistical multiparameter sensitivity measures for transfer gain and phase functions
Authors: Acar Cevdet 
Published: July 2007

AbstractNew statistical multiparameter sensitivity measures are defined for the transfer, gain and phase functions. The integrands of these sensitivity measures include mean values as well as variances of element variations. It is shown that a very simple relationship exists between transfer, gain and phase measures even though element variations are large. General formulae are derived for small element variations, which would simplify evaluation of the measures. These formulae are helpful in the comparison of various low sensitivity networks.
Minimizing the roundoff‐noise in digital filters by the branch and bound method
Authors: Lanfer H. , Lüder E. 
Published: July 2007

AbstractThe branch and bound method is used for minimizing the roundoff‐noise in cascaded 2nd‐order filter sections. The degrees of freedom are the pole‐zero assignment and the ordering of the stages in the cascade, whereas the structure chosen is always the 2D‐form. During the search an upper and a lower limit for the noise power provide an estimate of how close the solution is to the optimum. Thus, the search may be stopped if no further substantial improvement can be expected. The optimum is reached when the two limits coincide. The efficiency of the procedure is demonstrated by optimizing three filters with up to 22nd‐order transfer functions.
Efficient computation of frequency response of digital networks
Authors: Prasad K. P. , Reddy P. S. 
Published: July 2007

AbstractA major requirement in the analysis of multi‐input‐multi‐output digital networks is to compute the frequency response at a large number of points from a knowledge of the graph of a network with specified input and output nodes. Though the usual method of analysis by solving linear equations is more efficient than matrix inversion, solution of linear equations at each frequency may still require a large amount of computation. A more efficient method is to determine the poles and zeros of the desired system function and then calculate the frequency response from them. Though poles of the system function could be readily identified as contained in the eigenvalues of the state matrix of the network, difficulty is seen to arise in the determination of zeros which can not so easily be calculated. A simple and efficient method is proposed reducing the determination of zeros to a standard eigenvalue problem.
Design of stable two‐dimensional analogue and digital filters with applications in image processing
Authors: Ramamoorthy P. A. , Bruton L. T. 
Published: July 2007

AbstractA method is proposed for the frequency domain design of linear two‐dimensional analogue and digital filters with guaranteed stability. The technique used is based on the result that the numerator and the denominator of the input immittance of a two‐variable network (which is passive and lossy) are strictly Hurwitz polynomials. One of these strictly Hurwitz polynomials is assigned to the denominator of a two‐variable analogue transfer function and the network elements are then used as the variables of optimization thereby guaranteeing the stability of the analogue transfer function. The transfer function of the corresponding two‐dimensional discrete (digital) filter is obtained from the analogue transfer function by the bilinear transformation. Examples illustrating the versatility of the technique in designing 2D digital filters of arbitrary order approximating a given magnitude and group delay response are presented. These filters are used to process a simple binary image. The results obtained demonstrate the importance of linear phase in image processing applications.The method presented here can be extended to the design of stable m‐dimensional analogue and digital filters.
Generalized technique for designing broadband varactor‐tuned negative resistance oscillators
Authors: Rauscher Christen , Carlin Herbert J. 
Published: July 2007

AbstractA powerful method for designing broadband varactor‐tuned negative resistance oscillators is presented. The CAD procedure stems from a novel way of employing Hilbert transform techniques. The method is capable of realistically taking into account the decisive factors governing oscillator performance and directly processes measured large‐signal data of the active device without relying on an approximate circuit model for the device. Device—circuit interactions at higher harmonic frequencies are not considered in the context. A transferred‐electron oscillator design example is used to illustrate the method.
A unified theory of symmetry for nonlinear multiport and multiterminal resistors
Authors: Chua Leon O. , Vandewalle Joos 
Published: July 2007

AbstractSimple group‐theoretic concepts are used to develop a rigorous and comprehensive theory of symmetry for nonlinear multiport and multiterminal resistors which do not rely on geometrical arguments or other ad hoc techniques normally invoked in such studies. This theory unifies all forms of symmetry, including rotation, reflection and complementary symmetry, into a single framework. It also includes all known nonlinear symmetry principles as special cases. Moreover, a general method for identifying all symmetry characteristics possessed by a nonlinear multiport and multiterminal element is given.The main results of this paper:
Several algorithms for synthesizing a nonlinear multiport or multiterminal element having any prescribed form of symmetry are presented. In particular, various examples are given which illustrate how these algorithms can be used to derive well‐known symmetrical nonlinear circuit modules such as push‐pull amplifiers, complementary‐symmetric amplifiers, rectifiers, modulators, etc.;
A reduction algorithm is presented which allows a complicated symmetric element to be analysed by a much simpler reduced element;
A general principle is derived for applying symmetry to achieve frequency separation in nonlinear communication circuits where the even harmonic components are separated from the odd harmonic components.
Some new results on the controllability and observability of linear systems and networks
Authors: Lin P. M. , Kuo Y. L. 
Published: July 2007

AbstractThis paper introduces the concept of ‘hybrid‐dual systems’ and presents some new results on the controllability and observability of these systems. Theorem 1 states that for hybrid‐dual systems, which include dual systems as a special case, controllability of one implies observability of the other. Theorem 2 gives the topological conditions for RLC n‐ports such that controllability and observability imply each other. Theorem 2 also shows that for any RLC n‐port, observability implies controllability, but the converse is not true.
Nonconventional two‐port matrix decompositions and their realization
Authors: Moos Petr , Pospíšil Jiří 
Published: July 2007

AbstractGeneral conditions for sum and product matrix decomposition are applied to the sum of the chain matrices and the product of the immittance and the hybrid matrices. The corresponding connection of the partial two‐ports is realized by special three‐ports containing operational amplifiers and current and voltage controlled sources.
On the generation and optimization of equivalent ladder networks
Authors: Ulbrich W. , Dasch B. 
Published: July 2007

AbstractThe impedance scaling process and Norton's transformation are formulated in a uniform manner as a Cauer‐Howitt transformation with diagonal matrices. For passive two‐element‐kind ladder networks the realizability conditions are reduced to linear inequality constraints. An algorithm is given to enumerate all vertices of the realizability polyhedrons which represent all equivalent networks with a minimum number of elements. In addition a cost function meeting practical requirements is stated and optimized, taking into account various orders of network complexity.
Active rc filters using an operational transconductance amplifier and an operational amplifier
Authors: Deliyannis T. 
Published: July 2007

AbstractAn operational transconductance amplifier (OTA) and an operational amplifier are being used to synthesize various second‐order cascadable active RC filters. Two of them are active R filters. The filters are studied both theoretically and experimentally and are found to have low sensitivity to variations in their component values. They work satisfactorily in practice, except that some of them have a rather limited dynamic range.
A transmission line transformer having frequency independent matching properties
Authors: Roy Suhash C. Dutta 
Published: July 2007

AbstractIn this paper, we present a new transmission line transformer which is capable of matching a load resistance RL to a given source of internal resistance Rg in a frequency independent manner. This matching can be made perfect at all frequencies if RL/Rg = 4; for RL/Rg ≠ 4, the matching can still be made frequency independent but the power transferred to the load becomes less than the maximum available power.
Dual‐amplifier expansion and the design of very‐low‐frequency (VLF) hybrid integrated active filters
Authors: Moschytz G. S. , Horn P. 
Published: July 2007

AbstractThe problem of designing very‐low frequency (VLF) active filters in hybrid‐integrated form is discussed. It is shown that a class of single‐amplifier second‐order filters exists with which VLF active filters can be built while at the same time satisfying the constraints imposed by hybrid‐integrated circuit technology (i.e. limited resistor and capacitor values). However, with decreasing pole frequency, the gain required of the single amplifier becomes excessive, the gain‐sensitivity product (GSP) intolerably high. A solution to the problem is to introduce a second amplifier into the circuit and to distribute the required gain between the two amplifiers. This ‘dual‐amplifier expansion’ (DAX) significantly reduces the GSP, enhances the stability of the filter response, and reduces the susceptibility of the filter characteristics to nonideal amplifier effects. On the other hand DAX may not be arbitrarily introduced into a single‐amplifier circuit without taking the effect of the limited gain‐bandwidth product of the two amplifiers into account. It is shown that the degree by which the gain may be distributed between them is limited by the gain‐bandwidth product ratio of the two amplifiers. Much can be improved in this respect by proper frequency compensation of the two amplifiers. It is shown that a combination of the so‐called T‐compensation and the single‐pole single‐capacitor compensation produces results that are close to those obtainable with ideal amplifiers with unlimited bandwidth.
A new a priori ordering method for sparse systems of equations based on an ordered output set
Authors: Bhat Kabekode V. S. , Kinariwala Bharat 
Published: July 2007

AbstractIn the context of solution to the sparse systems of equations arising in computer‐aided analysis and design of electrical networks using the Gaussian elimination (GE) process it is well‐known that an a priori reordering for equations and unknowns is almost mandatory. In this paper we present a new approach for a priori ordering for the equations and unknowns using the theory of output sets. Our approach yields an ordered output set as the pivot sequence for an associated GE process. Our algorithm is simple and is more general than the existing ones and leads to an s‐minimal GE process. An example is presented for illustrating the algorithm and the computational complexity of the new method has been analysed. Additional work needed in the area is indicated.
The generalized chebyshev low‐pass prototype filter
Authors: Rhodes J. D. , Alseyab S. A. 
Published: July 2007

AbstractA synthesis method is presented for the class of low‐pass prototype filters having an equiripple passband response with a single transmission zero at infinity and the remainder at a finite real frequency. To synthesize the network, the even mode or the odd mode is obtained directly using the alternating pole technique and little accuracy is lost for networks up to degree 19. Tables of element values for commonly used specifications are included. Finally, the practical advantages of this prototype when used to design certain classes of filters are discussed.
Synthesis of symmetrical dual mode in‐line prototype networks
Authors: Rhodes J. D. , Zabalawi I. H. 
Published: July 2007

AbstractAn analytic synthesis technique is developed for symmetrical dual mode in‐line prototype networks up to and including degree 12 networks. Due to the symmetrical realization, the even mode coupling matrix completely defines the network and one particular form representing the double cross‐coupled array, may be obtained directly from the transfer function. Commencing with this matrix, rotational transformation are used to transform the even mode matrix into the form required for a dual mode in line structure. Analytical solutions are obtained for degrees up to and including 12 and the necessary realizability conditions are determined for each case. Explicit formulas for the angles of rotation are given and for degrees up to and including 10, a complete set of explicit formulas are provided for the final coupling matrix. To assist in the design of the in‐line structure, tables of element values for filters having 20 dB and 26 dB return loss and possessing the minimum number of transmission zeros at infinity are tabulated.
Multiple real‐pole equal‐ripple rational (MRPER) approximation for lowpass RC‐active filters
Authors: Biey Mario , Premoli Amedeo 
Published: July 2007

AbstractA new class of lowpass rational transfer functions is defined, with equal‐ripple behaviour both in the passband and in the stopband. The proposed functions have a multiple real pole, which allows the realization of lowpass RC‐active filters by cascading more (than one) 3rd‐order blocks.These new functions, called multiple real‐pole equal‐ripple rational (MRPER), improve the attenuation performance with respect to a classical solution employing the same number of 2nd‐order blocks and hence may allow a reduction in the required number of active elements and, eventually, in power consumption and in noise‐to‐signal ratio. However, even if the number of active blocks cannot be reduced, the better attenuation performance, which results, allows component tolerances to relax.
Orthogonal cascade realization of real multiport digital filters
Authors: Deprettere E. , Dewilde P. 
Published: July 2007

AbstractA generally applicable theory for multiport orthogonal digital filter synthesis is discussed, using a direct algebraic method. Standard (complex) degree 1 and irreducible (real) degree 2 chain scattering matrices are derived and the computability problem which normally occurs in such filters is discussed and solved for the general case. It is shown that any finite causal and lossless real multivariate system can be realized as a computationally compatible cascade of real degree 1 and degree 2 factors consisting of an orthogonal constant interconnecting part and a lossless dynamic portion. In order to increase the practical interest of the paper, realizations of these sections are explicitly given. The known scalar wave digital filter ‘adaptors’ emerge as a special case of the theory presented in this paper. The general results are of interest in multiport digital signal processing, in multivariate interpolation theory and in multichannel prediction and modelling theory and techniques.
Passive approach to switched‐capacitor circuits
Authors: Martinelli G. , Salerno M. 
Published: July 2007

AbstractThe possibility of developing a passive approach to switched‐capacitor circuits is explored in the present paper with particular reference to the determination of a valid scheme for the parallel LC resonator and for the inductor. The schemes proposed for these switched‐capacitor components are shown to be valid in the typical situations of operation. The results of several tests, carried out both on prototypes and on the digital computer by simulation, illustrate the behaviour of the proposed circuits and confirm their effectiveness.
Contribution to the qualitative theory of non‐linear systems and networks
Authors: Szatkowski Andrzej 
Published: July 2007

AbstractThis paper deals with the qualitative theory of non‐linear systems and networks. Several theorems on the boundedness of the solutions and on the stability of equilibrium points are proved. The problem of the synthesis of non‐linear systems and networks with the prescribed trajectories is considered. Some geometric properties of the limit sets of the solutions are presented.
Classification and generation of active compensated non‐inverting VCVS building blocks
Authors: Soliman Ahmed M. 
Published: July 2007

AbstractIt is shown that the active compensated non‐inverting voltage controlled voltage source (VCVS) structures employing two operational amplifiers (op‐amps) may be classified into two major classes. Class 1, in which the phase compensation condition does not depend on the unity‐gain bandwidth of the op‐amps used, and class 2, in which the phase compensation condition depends on the unity‐gain bandwidth of both op‐amps. Detailed comparison tables which include the condition for phase compensation, the phase error, the magnitude error and the realizable bandwidth are given.
Hierarchic decomposition method for the topological analysis of electronic networks
Authors: Starzyk Janusz , Sliwa Edward 
Published: July 2007

AbstractThis paper concerns a new approach to the topological analysis of linear networks. It gives a description of the hierarchic decomposition method (i.e. multiple decomposition of a decomposed network) which can be applied in computer analysis of electronic networks. A new universal algorithm for generation of k‐trees is presented.
The impact of generalized symmetry on computer‐aided design of cascaded structures
Authors: Bandler J. W. , Biernacki R. M. , Rizk M. R. M. 
Published: July 2007

AbstractNew theoretical and computational tools are presented which deal with generalized symmetry concepts related to the computer‐aided design of cascaded structures. The presentation includes the computational implications of networks consisting of symmetrically located reverse adjoint subnetworks with and without scaling, as well as antisymmetry. Formulas presented are designed to be used in simulation, sensitivity and tolerance analyses as well as in optimal design.
Floating inductor with two current conveyors
Authors: Patranabis D. , Paul A. N. 
Published: July 2007

AbstractThere have been considerable efforts towards the realization of ideal floating inductors where mostly three active blocks are required. The reduction in the number of active blocks to two was however achieved with considerable increase in the number of resistances and passive parameter constraints. The proposed scheme suggests a method to produce a floating inductor with a series negative resistance using two current conveyors, only three resistors and one capacitor, involving only one restrictive constraint. The realized inductor was also used to design a third order Butterworth filter. Experimental results confirm the applicability of the realized immittance.
Algorithms for solution updating due to large changes in system parameters
Authors: Hajj Ibrahim N. 
Published: July 2007

AbstractA set of algorithms for solution updating due to large changes in system parameters is derived. The algorithms are derived by partitioning the changes in the values of the elements from the remainder of the system and then applying tearing procedures to solve tthe partitioned system of equations. The algorithms obtained include new ones as well as most of the previously proposed ones for solving this problem. Sparse matrix solution techniques are used whenever possible, and the computational requirements of the algorithms are assessed and compared.
Transmission parameter representation of non‐uniform transmission line Green's functions
Authors: Haley Stephen B. 
Published: July 2007

AbstractThe Green's function G(x, x') of a non‐uniform transmission line is formulated exactly in terms of partial transmission matrix parameters associated with different segments of the line. Exact differential expressions relate the transmission parameters to each other, and it is shown that G(x, x') can be expressed entirely in terms of a single transmission parameter B(x, x') and its derivatives. The voltage response V(x) on any doubly‐terminated line with arbitrary current source density along the line is given. A new perturbation technique, based on a Volterra integral equation, is developed which determines V(x) in terms of known functions and arbitrary perturbing immittances on the line.
Singular perturbations in the state space approach of linear electrical networks
Authors: Sannuti P. 
Published: July 2007

AbstractNetworks whose dynamic order is less than the number of energy storing elements they contain are considered. By adding parasitic elements, their dynamic order is restored. After selecting the state variables properly, singular perturbation theory is used to analyse the network behaviour with respect to the parasitic elements and to calculate the initial jumps in the network variables. Parasitic elements are seen to play a dominating role in dictating the stability of a network. The need for generalizing the presently available singular perturbation theory is pointed out by means of an example.
The adjoint switched capacitor network and its application to frequency, noise and sensitivity analysis
Authors: Vandewalle J. , De Man H. , Rabaey J. 
Published: July 2007

AbstractGiven a linear network of capacitors, periodically controlled switches and sources we derive its adjoint network and show how it can be used to reduce the computational complexity of the frequency, noise and sensitivity analysis.The construction of the adjoint switched capacitor circuit turns out to be quite simple, even for switched capacitor networks with more than two phases or with a continuous input‐output path. Moreover this construction can be performed equivalently in the time domain or on the equivalent circuit.In order to facilitate the implementation in a computer‐aided‐design program all derivations are performed in the modified nodal analysis formulation (MNA).