bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiple‐critical‐pole coupled active filters
Authors: Mijat N. , Moschytz G. S. 
Published: July 2007

AbstractIn this paper realizations of low sensitivity narrow BP active filters implementing multiple‐critical‐pole (MCP) approximation methods and coupled filter structures are studied. In the first part of the paper, a synthesis procedure particularly developed for the realization of MCP transfer functions is described. According to that procedure the portion of the MCP transfer function containing multiple poles is realized as a follow‐the‐leader feedback (FLF) network, and the remaining part as a cascade. It is shown that the lower sensitivities of MCP functions in comparison with standard approximating functions (Butterworth, Chebyshev, etc.) can be further decreased by applying the FLF configuration instead of the cascade. the synthesis procedure is straightforward and in some cases it can be performed using identical second‐order BP blocks. the final circuit sensitivities can be optimized according to given filter specifications and a user selected optimization criterion.In the second part of the paper, the MCP transfer functions are combined with the cascaded biquarts (CBQ), the shifted companion form (SCF), and the leap‐frog (LF) structures, and sensitivity analysis is performed. It is shown that applications of the above mentioned structures can improve the filter sensitivites in a way similar to that of the given FLF configuration.
Double broadband matching and the problem of reciprocal reactance 2n‐port cascade decomposition
Authors: Youla D. C. , Carlin H. J. , Yarman B. S. 
Published: July 2007

AbstractLet 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.
Integral manifolds for non‐linear circuits
Authors: Odyniec M. , Chua L. O. 
Published: July 2007

AbstractAlthough the theory of integral manifolds is well known among applied mathematicians as a powerful tool in non‐linear oscillations, it is relatively unknown, let alone applied, among circuit engineers. the purpose of this mostly tutorial paper is to illustrate the applications of integral manifolds to explain various non‐linear phenomena widely observed in non‐linear circuits. Numerous examples and graphical illustrations are included in order to present the theory with a minimum amount of mathematics.
Negative resistance devices: Part II
Authors: Chua L. O. , Deng An‐Chang 
Published: July 2007

AbstractAs a sequel to Reference 1, this paper presents new analytical and topological guidelines for synthesizing negative‐resistance devices. Among other things, these guidelines can be used to tune the devices by varying the magnitude and dynamic range of the negative (small‐signal) resistance.Necessary and sufficient conditions are given for a circuit containing only one bipolar transistor and linear reciprocal passive two‐ports (e.g. ideal transformers) to exhibit a negative resistance. In the special case where the circuit contains only one ideal transformer, one transistor and linear positive 2‐terminal resistors, an equivalent topological criterion which can be checked by inspection is given.Finally, three canonical negative‐resistance one‐ports containing two identical bipolar transistors, linear positive 2‐terminal resistors and batteries are synthesized to exhibit an odd‐symmetric (hence active) voltage‐controlled or current‐controlled v‐i curve.
Uniqueness of the steady state for small source amplitudes in non‐linear non‐autonomous circuitsc
Authors: Hasler Martin , Verburgh Philippe 
Published: July 2007

AbstractThe purpose of this paper is to give a sufficient condition for the uniqueness of the steady state for circuits that are composed of strictly locally passive capacitors and inductors, of time‐dependent bounded voltage and current sources and of a resistive N‐port that is strictly locally passive and eventually strictly passive. It is an extension of previously obtained results by the same authors, where strong local passivity was required. the new condition allows one to give a bound on the source amplitudes below which passive elements. It also gives a more explicit content to a theorem by Chua and Green which states that for sufficiently small source amplitudes the steady state is unique. the new condition is obtained by giving explicit uniform eventual bounds on the solutions as t → ∞, which are of independent interest. Two examples illustrate that the various explicit bounds can easily be computed in concrete examples.
Static global models for linear n‐port networks realized with operational amplifiers
Authors: Hueratas J. L. , Rueda A. , Rodriguez‐Vazquez A. 
Published: July 2007

AbstractThis paper is addressed to obtaining global models for the circuit realization of a given linear multiport implemented using operational amplifiers. It is conventional to consider a linear characterization for such multiports, the consequence being a restricted validity for the model. In other words, this model is meaningful only for inputs that do not lead any operational amplifier into saturation. It is a serious drawback, mainly when the linear n‐port has to be embedded of the actual circuit can be very inaccurate leading to problems that cannot be explained by a linear model.In the work reported herein, two main results must be remarked. One is the procedure for developing explicit global descriptions for two general circuit topologies. the other is concerned with the dependence existing between the circuit topology and the type of model to be deprived. In that sense, it is interesting to note the close relation of our global models with the canonical piecewise‐linear descriptions derived in Reference 12. Extension to piecewise polynomial models is also considered in some detail.
Modelling non‐linear devices exhibiting frequency‐dependent capacitances and inductances
Authors: Dervişoǧlu A. , Chua L. O. 
Published: July 2007

AbstractThe incremental capacitance and inductance of many electronic devices are frequency‐dependent. This paper presents a systematic method for modelling such devices using only positive and/or negative linear time‐imvariant capacitances and inductances.Modelling of a frequency‐dependent capacitor or inductor is reduced to the realization of an odd rational function. It has been shown that any odd rational function can be realized as the driving‐point function of a ± L, ± C one‐port. It has also been shown that a linear higher‐order capacitor or inductor of order 2k + 1 can be realized by a ± L, ± C one‐port which contains 2k + 2 elements.
Analogue circuits fault dictionary—new approaches and implementation
Authors: Lin P. M. , Elcherif Y. S. 
Published: July 2007

AbstractThe d.c. fault dictionary approach has been found very useful for diagnosing hard failures (open circuits and short circuits) in non‐linear analogue circuits. In this paper we present the use of several techniques to enhance the capability of the d.c. fault dictionary. These include (1) modelling all non‐linearities by piecewise linear characteristics, (2) solving the piecewise linear resistive network by Lemke's complementary pivot algorithm, (3) using multilevel logic operation to compile an integer‐code fault dictionary which totally eliminates any post‐test calculations. the automatic generation of a fault dictionary for a video amplifier by the use of the computer program HAFDIC is described.
A systematic approach to the realization and design of actively compensated two OA voltage amplifiers
Authors: Lopes Paulo B. , Bhattacharyya B. B. 
Published: July 2007

AbstractSeveral actively compensated voltage amplifiers (ACVAs) employing two operational amplifiers have been reported separately in the recent literature. In this article, the results of a systematic and comprehensive study of both non‐inverting and inverting such ACVAs are presented. Using a combination of practical and theoretical considerations, ACVAs are first divided into classess. Each class is further divided into types. Realizability conditions are then derived for each of the different types. These conditions lead directly to a set of useful realizations. the performance of each realization is considered in detail with respect to several practical considerations of interest, such as magnitude and phase errors, effect of the second pole of the operational amplifiers (OAs), tunability, maximum signal handling capability, etc. the results of practical experiments are also given. Experimental results agree closely with the theoretical predictions.
Smoothing over the intervals of orthogonally sampled signals
Authors: Halpern Peter H. , Mallory Peter E. 
Published: July 2007

AbstractA method for smoothing and interpolating a Fourier sine series representation of a continuous signal is developed to take advantage of the relative ease with which since pulse forming networks can be built. With this method it is possible both to accurately approximate the signal at the points where the sine harmonics are all zero and to smooth the signal. A method is also developed to combat round‐off error in the extraction of the harmonic coefficients, and an expression is derived for the maximum error in the representation. Finally, examples are presented to show the effectiveness of this method.
Canonical piecewise‐linear analysis: Generalized breakpoint hopping algorithm
Authors: Chua Leon O. , Deng An‐Cheng 
Published: July 2007

AbstractAs an extension to the breakpoint hopping algorithm developed in reference 1, the algorithm presented in this paper efficiently solves the d.c. problem for finding the d.c. operating point(s) and for tracing the driving‐point and transfer characteristics of an extremely broad class of non‐linear resistive circuits. In particular, bipolar and MOS transistor circuits are included. A user‐friendly C program has been written to implement this algorithm where the input format for describing the circuit is compatible with the SPICE program.
Exact sensitivity analysis for optimization of multi‐coupled cavity filters
Authors: Bandler J. W. , Chen S. H. , Daijavad S. 
Published: July 2007

AbstractThis paper describes an efficient approach to the simulation and exact sensitivity evaluation of multi‐coupled cavity filters. The approach uses sensitivity formulae for such responses as input or output reflectron coefficient, return loss, insertion loss, transducer loss, gain slope and group delay, which are derived for a two‐port equivalent of a general network described by its symmetrical impedance matrix. The formulae are specialized to the case of multi‐coupled cavity filters, using a filter model which takes into account many non‐ideal factors such as losses, frequency dependent coupling parameters and stray couplings. The formulation also treats synchronously or asynchronously tuned structures in a unified manner. Explicit tables of first‐ and second‐order sensitivities w.r.t. all variables of interest, including frequency, are presented. Three problems of significant practical value in manufacturing of multi‐cavity filters are solved with the direct application of our formulae. A 10th‐order filter is considered for all three cases. The first case is simultaneous optimization of the amplitude and delay responses to obtain a self‐equalized filter. The second case is accurate prediction of the responses for a lossy filter by simulating a lossless filter. The third case involves parameter identification of the filter from simulated measurements on its responses.
Theory of perturbed negative conductance oscillators
Authors: Thirup G. 
Published: July 2007

AbstractAn oscillator is considered as a mixing circuit where the voltage of the oscillator is the local oscillator voltage. A sinusoidal perturbation is applied to the oscillator, exciting current and voltage components at frequencies equivalent to signal, intermediate and image frequencies in a normal mixing circuit. The relationship between the components can be described by three linear equations whose determinant is zero for a d.c. perturbation and for perturbations having the oscillator frequency. By means of the three linear equations the stability, mixing, modulation and demodulation of an oscillator are treated (Section 2). The stability conditions are shown to be the same as those derived by Kurokawa in another way (Section 3). Perturbations of a Van der Pol oscillator are investigated in detail. It is shown that the oscillator obtains a high dynamic Q at small oscillator voltages, and that the sensitivity of a self‐detecting oscillator to load perturbations is independent of the oscillator voltage (Section 4). The signal‐to‐noise ratio of a perturbed oscillator is considered and the conditions for the highest signal‐to‐noise ratio are given (Section 5). Finally, some of the difficulties encountered in making perturbed oscillators for microwave spectrometers are mentioned (Section 6).
The double scroll bifurcations
Authors: Matsumoto T. , Chua L. O. , Komuro M. 
Published: July 2007

AbstractThis paper describes the dynamics of the simplest physical system known to date whose chaotic dynamics and rich bifurcation phenomena have been observed not only in the laboratory, but also reconfirmed by extensive computer simulation of its associated mathematical model: a 3rd‐order autonomous ordinary differential equation. The physical system is a 5‐element electrical circuit whose only non‐linearity is a non‐linear resistor characterized by a 3‐segment piecewise‐linear voltage‐current characteristic.Despite the simplicity of the circuit, however, it is imbued with an extremely rich variety of bifurcation phenomena. By changing the capacitance values, many phenomena, including Hopf bifurcation, period‐doubling cascades, Rössler's spiral‐type and screw‐type attractors,4 periodic windows, ‘double‐scroll’ attractor,1 boundary crisis,5 Shilnikov‐type phenomenon,6 etc. have been observed experimentally and confirmed by computer simulation. Other attractors and periodic windows have also been observed by varying the conductance values.In addition, Rössler's spiral‐type and screw‐type attractors have been observed from the same circuit, where the non‐linear resistor has only one break point, i.e. it is described by a 2‐segment piecewise‐linear v‐i characteristic. This means that extremely complicated non‐periodic (chaotic) waveforms can arise in the simplest third‐order uncoupled electrical circuit in which all elements except one (a resistor) are linear and passive, and in which the constitutive relation of the non‐linear resistor is made of the simplest conceivable non‐linearity, namely 2 straight‐line segments.
Block parallel processing of 2‐D digital signals
Authors: Mertzios B. G. 
Published: July 2007

AbstractA structure is presented for the processing of two‐dimensional digital signals, based on a block state‐space model. Specifically the proposed structure exhibits high inherent parallelism since the state‐space model is properly split into a number of parallel subfilters. A detailed analysis is done to achieve a balanced distribution of the necessary non‐trivial multiplications in the subfilters. The optimal block dimensions are determined in order to minimize the critical number of non‐trivial multiplications per output sample. Finally an estimation of the data throughput delay, based on the number of necessary multiplications and additions, is given for the proposed structure. It is shown that the data throughput delay, estimated in the case of optimal block dimensions, is increased almost linearly with the filter's order and is substantially reduced relative to that which has been estimated with the canonical state‐space model. Also the data throughput delay for suboptimal block dimensions are considered. The proposed model is ideally suited to computer use and VLSI implementation.
Solutions for a three‐dimensional non‐linear stabilized oscillator
Authors: Daboul J. , Kaplan B. Z. 
Published: July 2007

AbstractA system of coupled non‐linear equations, describing a three‐phase stabilized oscillator, is analysed by introducing ‘cyclotomic’ co‐ordinates. We show that this system, under certain conditions, approaches asymptotically non‐conservative linear systems; and yet it does have stabilized solutions (limit cycles). The non‐linear system is solved analytically for an important class of stabilizing functions. We show that the frequency ω of our oscillator responds instantaneously to changes of certain parameters. This result has useful applications in building quickly responding novel electronic voltage‐controlled oscillators.
Efficient realization of pulse‐shaping networks by employing asymmetric reference wave‐forms with fixed spectral envelopes
Authors: Kishi Genya , Sakaniwa Kohichi , Takei Yoshiyuki 
Published: July 2007

AbstractThis paper considers the application of an asymmetric trapezoidal wave‐form to the realization of pulse‐shaping networks.The first part of the paper shows that a trapezoidal wave‐form can be asymmetrized, keeping its spectral upper bound invariant. More precisely, we have proved that the upper bound of the spectral envelope does not change if the average of the leading and trailing slopes of a trapezoidal wave‐form is kept constant.In the remaining part of the paper, it is shown that an asymmetric reference wave‐form is very effective in designing pulse‐shaping networks, i.e. in many time‐domain synthesis methods a better approximation is obtained by using an asymmetric reference wave‐form with a compressed leading edge.
Successive approximation logarithmic A/D conversion using charge redistribution techniques
Authors: Lefas C. C. 
Published: July 2007

AbstractThe present paper describes a logarithmic A/D converter (LADC) working with the charge redistribution principle. the LADC uses a serial and a parallel capacitive attenuator and is suitable for manufacturing on a single chip. Formulae for the values of the capacitors are given in terms of the base of logarithm used. This LADC uses logarithmically spaced voltage comparison levels and therefore eliminates the use of logarithmic analogue signal conditioning circuits.
Generalized ladder synthesis by subnetwork removal
Authors: Mou‐Yan Zou , Unbehauen R. 
Published: July 2007

AbstractA general procedure is presented to realize a two‐port impedance matrix by a generalized transformerless LC ladder network including the classical LC ladder structure as a special case. the realization process consists of repeatedly applying a subnetwork removal cycle for which six different cases are to be considered. the feasibility of the various subnetwork removals is characterized by formulating necessary and sufficient conditions on the impedance matrix. the application of the procedure is illustrated by a numerical example.
Fully integrated active‐Rc filters using mos and non‐balanced structure
Authors: Acar C. , Ghausi M. S. 
Published: July 2007

AbstractA technique for implementing fully integrated continuous time non‐switched capacitor filter has been recently reported in the literature. the technique uses a balanced structure using op‐amps, capacitors and MOS transistors operated in the non‐saturated region as voltage‐controlled resistors. In order to eliminate the non‐linearity of the MOS transistors over an extended voltage range the current techniques use fully balanced circuits. This paper provides a simple technique for cancellation of non‐linearities, thereby reducing the number of elements, and proposes several simple circuits. the technique is then used in the design of high‐order filters.
Design of testability for analogue fault diagnosis
Authors: Wey Chin‐Long 
Published: July 2007

AbstractWith the rapidly increasing complexity of circuits and systems, the ability adequately to design a diagnosable circuit or system is a prime requisite for rapid fault location. In the present paper, a necessary and sufficient condition for pseudo‐circuit generation is presented for the use of the pseudo‐circuit in the self‐test algorithm. to determine the diagnosability of a designed circuit, a testability condition is presented with examples. the unique feature of these conditions is that they depend only on the topological structure of a given circuit, not on the component values; therefore, these conditions can be implemented in both linear and non‐linear circuits or systems. With the aid of a computer, the test points may be generated automatically by the proposed algorithm. Based on the proposed algorithm, the design of testability can be established.
A simple dynamic circuit model for mos structure
Authors: Chua Leon O. , Chang Chwen‐Cher 
Published: July 2007

AbstractA new simple circuit model for the MOS (metal‐oxide‐semiconductor) structure is presented. the model consists of three elements, namely, a linear capacitor, a non‐linear capacitor and a C‐dynamic element. Each component bears a simple relationship to the physical operating mechanism inside the MOS structure. the model can be used for simulating arbitrary MOS structure circuits under all operating conditions. In particular, it is capable of reproducing the structure's frequency‐dependent small‐signal characteristics. the model is also shown to exhibit many important and interesting dynamic behaviours under forward, reverse and sinusoidal operating modes.The model is based mainly upon the device's physical operating principles. But perhaps the most significant implication of this model is that it is the first ever to use a dynamic element to model the MOS structure from a physical approach.
Topological conditions for a resistive circuit containing negative non‐linear resistors to have a unique solution
Authors: Nishi Tetsuo , Chua Leon O. 
Published: July 2007

AbstractNecessary and sufficient conditions are given for resistive circuits containing both monotone‐increasing non‐linear resistors and monotone‐decreasing non‐linear resistors (called negative non‐linear resistors), in addition to controlled sources and op‐amps, to have a unique solution for all circuit parameters. Several theorems are given for various classes of circuits containing different combinations of active circuit elements. the theorems are couched mostly in topological terms and can therefore be checked by inspection.
Simple proofs of some discrete domain stability related properties of multidimensional polynomials
Authors: Basu S. , Fettweis A. 
Published: July 2007

AbstractSimple and rigorous proofs of results due to various authors on tests for the property that a multivariable polynomial be devoid of zeros in the closed unit polydisc are given. the proof technique rests largely on a correct and complete formulation of the fact that the zeros of a polynomial are continuous functions of its coefficients. It is shown that almost all other related results can be derived in this manner.