By Topic

Circuits and Systems, IEEE Transactions on

Issue 9 • Date September 1987

Filter Results

Displaying Results 1 - 25 of 26
  • Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comments on "Multitone Signals with Low Crest Factor

    Page(s): 1125 - 1127
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (320 KB)  

    A few comments are made to help clarify the subject of the above paper' and to point out some misleading statements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Homoclinic and heteroclinic orbits in the double scroll attractor

    Page(s): 1115 - 1120
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    Chua, Matsumoto, and others have reported extensive simulation studies on a piecewise-linear model of a simple circuit. There is strong numerical and experimental evidence for chaotic behavior. This paper shows that the observed behavior can be understood using the theory of Shil'nikov bifurcations of homoclinic and heteroclinic orbits. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A general continued fraction expansion of 1-D complex lossless positive real function with application to 2-D

    Page(s): 1121 - 1122
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (248 KB)  

    This letter presents a general continued fraction expansion for complex reactance functions. The application of the method to test the 2-D Hurwitz nature is indicated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Balanced realization of orthogonally symmetric transfer function matrices

    Page(s): 997 - 1010
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1472 KB)  

    Structural properties of minimal balanced realizations of orthogonally symmetric transfer function matrices are developed. These properties are then used to formulate a computationally efficient algorithm for determining balanced realizations of transfer function matrices in this class. The applicability of these realizations to circuit synthesis is indicated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design of FIR filters as a tapped cascaded interconnection of identical subfilters

    Page(s): 1011 - 1029
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2096 KB)  

    A general theory is presented for the design of linear-phase FIR digital filters as a tapped cascaded interconnection of identical FIR subfilters. The approach is an extension of the Kaiser-Hamming procedure [1] proposed for sharpening the response of an FIR filter. The new approach allows the subfilter and the tap coefficients to be simultaneously optimized to minimize either the number of subfilters for the given order of the subfilter or the subfilter order for the given number of subfilters. The optimization is based on the use of standard FIR filter design algorithms. Several examples demonstrate how the new approach leads to implementations requiring significantly fewer distinct multipliers than equivalent direct-form minimax FIR designs at the expense of a slight increase in the overall filter order. The number of distinct multipliers can be reduced to approximatelysqrt{2.6L}, whereLis the order of the direct-form minimax design. Alternatively, the design of the subfilter and tap coefficients can be separated. This makes it possible to construct the subfilter so that it roughly meets the overall specifications with a highly reduced number of arithmetic operations. In this case, the tap coefficients are optimized to minimize the required number of subfilters to meet the given criteria. Even multiplier-free designs can be obtained by carefully constructing the subfilter and determining the tap coefficients. Several structures are discussed for implementing the overall filter. These structures are compared with each other and with equivalent directform minimax designs in terms of the number of distinct multipliers, overall filter order, overall multiplication rate, number of delay elements, coefficient sensitivity, and output noise variance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Block realization of multidimensional IIR digital filters and its finite word effects

    Page(s): 1030 - 1044
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1528 KB)  

    This paper describes the formulation and realization of multidimensional block systems and investigates their stability and numerical performance. The block system can be constructed by the concept of block shift invariance. It possesses the general property that if(lambda_1,lambda_2,cdots,lambda_N)is a pole of the original scalar system, then(lambda^{L_1}_{1},lambda^{L_2}_{2},cdots,lambda^{L_N}_{N}will be a pole of the block system, whereL_i, is the block length in theith tuple. Thus, a stable scalar system will guarantee that its extended block systems are stable. Two methods of deriving block transfer functions from a given scalar transfer function are proposed. Moreover, it is shown that the scalar transfer function can be derived from its extended block transfer function. Based on Givone-Roesser's model, a unified approach of establishing 1-D toN-D block state-space models is presented. It is shown for the proposed block model that the dynamic range constraint in each tuple is invariant under block extension. In addition, the average roundoff noise variance due to the rounding errors in theith tuple is reduced by a factor equal to the block length in this tuple when compared with its scalar counterpart. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Theory and applications of all-digital N-path filters

    Page(s): 1045 - 1052
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (824 KB)  

    The all-digitalN-path filter structure for the processing of discrete-time signals is introduced. The structure is made ofNparallel paths having identical time-invariant digital filters. The filters are connected to a common input signal path through input modulators, and a common output signal path through output modulators. The modulators produce identical periodic sequences but are staggered in phase from filter to filter. A detailed time-domain and frequency-domain analysis of theN-path filter is provided. It is shown that for certain bandlimited modulating sequences, or by appropriately bandlimiting the input and output signals, the overall time-varying structure can be made to appear as a timeinvariant network. This approach leads to filters with adjustable characteristics, and it is shown that by time-sharing the time-invariant digital filter pathNtimes, it is possible to design filters with complex characteristics quite economically. A number of useful modulating functions are described, and some possible applications are discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A design method for pulseshaping filters having small intersymbol interference

    Page(s): 1137 - 1138
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (136 KB)  

    A realizable filter of degreeNis specified by its poles and residues. Being given theNpoles, the problem of calculating the residues such that intersymbol interference is minimal is treated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Class E Power Amplifiers and Frequency Multipliers with finite DC-Feed Inductance

    Page(s): 1074 - 1087
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1384 KB)  

    Previous descriptions of class E amplifiers and frequency multipliers have required a radio frequency choke between the dc power supply and the active device "switch." In this paper, it is shown that class E operation may be maintained with the RF choke replaced by a smaller reactance. The analysis technique used is similar to that used by Raab in his description of class E amplifiers in that the equations describing circuit operation are obtained from Fourier series methods and the assumption of an infinite output networkQ. The equations so obtained are used to determine (1) optimum operation (maximum power output capability at 100-percent efficiency) at any harmonic and (2) design equations that yield the requisite component values for optimum operation. The equations show that class E circuits may be configured to accommodate devices with arbitrary output capacitance and that class E amplifiers may be configured to provide greater power output capability than can be obtained using an RF choke design. Class E circuits with moderate values of output networkQwere constructed and tested. The measured performance of these experimental circuits shows excellent agreement with the theoretical performance predicted by the equations. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On a new measure of system diagnosability in presence of hybrid faults

    Page(s): 1053 - 1058
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (896 KB)  

    This paper deals with the problem of testing the diagnosability of a system when the units of the system may fail permanently or intermittently. It takes into account the fact that different units of a system have different probabilities of failing permanently and intermittently. For each unit, these probabilities are computed assuming a continuous parameter Markov model. It has also been shown that, with this choice of model, the incompleteness of diagnosis (i.e., an intermittently failing unit classified as faultfree) can be avoided up to any level of confidence. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multivariable mirror-image and anti-mirror-image polynomials obtained by bilinear transformations

    Page(s): 1088 - 1090
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (344 KB)  

    In this paper, some properties of the multivariable mirrorimage and anti-mirror image polynomials will be studied when they are obtained by bilinear transformations from the corresponding even and odd parts of a multivariable polynomial. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A comparison of two models for an oscillator with an amplitude control system

    Page(s): 1110 - 1112
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (344 KB)  

    Two models are compared which describe amplitude transients in an oscillator with an amplitude control system. The approximate model is a linearization of the more complicated exponential model. Using an amplitude control system that employs squaring circuits to derive the control signal, the two equations are solved in closed form and the transient responses are compared. It is found that the transient duration for the approximate model is longer and that the difference between the two models increases as the initial amplitude decreases. When a loop filter, with time constanttau, is introduced similar results are found. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Josephson 2-bit arithmetic logic unit

    Page(s): 1123 - 1124
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB)  

    A Josephson 2-bit arithmetic logic unit (ALU) is presented. A four-junction logic (4JL) gate-family is used in the ALU circuit. The ALU circuit is designed based on a dual-rail logic to perform both the arithmetic and the logic functions. The circuit was fabricated with Nb/Al-oxide/Nb tunnel junctions using a 3-{mu}mminimum line width technology. For each 16 functions, the circuit was completely confirmed in consistent logic operations. The operating time was measured to be 165 ps in the arithmetic function of subtraction,AminusB. Power dissipation was estimated to be 581{mu}Win the circuit. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Time and call limited telephone problem

    Page(s): 1129 - 1131
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (432 KB)  

    The structure and the minimum distribution time of the channel graph for the telephone problem of a minimum number of calls and minimum distribution time are determined. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Channel routing with provably short wires

    Page(s): 1133 - 1135
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB)  

    An algorithm that routes any two-terminal net channel routing problem with each wire being at most twice its minimum length is presented. Thus, fast propagation of the signals along the wires is ensured. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stability of systems with multiple very small and very large parasitics

    Page(s): 1107 - 1110
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (536 KB)  

    Stability of linear systems with several very small as well as several very large parasitic parameters is analyzed. Time-scale separation is used in conjunction with the recently introduced notion of strongD-stability to prove general asymptotic stability results for this class of systems. Moreover, it is observed that, contrary to the case studied by Desoer and Shensa (1970) which involved a single small parasitic parameter and a single large parasitic parameter, the system cannot be transformed into a standard multiparameter singular perturbation problem. Hence, systems containing both stray and sluggish elements do indeed represent a separate class of problems in asymptotic analysis. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Some direct interconnections between formal language theory and discrete-time linear system theory

    Page(s): 1102 - 1107
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (920 KB)  

    In an attempt to bridge the gap between theoretical computer science and, system theory, three problems from developmental system theory are discussed in parallel with the corresponding problems for discrete-time linear systems. The question of existence of algorithmic solutions to each of the problems is investigated. Based on elementary linear algebra, it is shown that each of the three problems is decidable for discrete-time linear systems while the equivalent problems for developmental systems are either undecidable or the existence of algorithmic solutions is an open problem. Developmental systems are studied in both theoretical biology and formal language theory so the discussion presented in this paper provides some fundamental links between these two subjects and linear systems theory. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel 2-D window for spectral estimation

    Page(s): 1112 - 1115
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (464 KB)  

    A novel 2-D window can be easily generated by the McClellan transform of Tseng's 1-D window. The transformed window has nearly circularly symmetric frequency response and preserves the features and flexibility of Tseng's 1-D prototype window. It can independently control the pattern falloff rate, the sidelobe level, and the depth of a steerable wide dip. Examples of detecting multiple 2-D closely spaced sinusoids have demonstrated the superiority of this novel 2-D window. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the transformation of RC-active oscillators

    Page(s): 1091 - 1093
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB)  

    It is shown that some recently proposed transformations pertaining to single op-amp oscillators may be viewed as a consequence of a more general property applicable to all RC-active oscillators (of any order and employing any number of active and passive elements) presented here in the form of a theorem. Since the theorem is proved in terms of nullors, the result is quite general and may also be applied to oscillators employing other kinds of devices which can be modeled by nullors. Some examples of practical interest are outlined. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the optimal state estimation of a class of discrete-time nonlinear systems

    Page(s): 1127 - 1129
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (384 KB)  

    The optimal linear estimator is given for a class of discretetime nonlinear stochastic systems with nonlinear noisy measurement equations. First, the one-step predictor is considered and then the limiting behavior of the estimator is examined. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The dual double scroll equation

    Page(s): 1059 - 1073
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1704 KB)  

    This paper extends the Poincaré half-map technique, developed for the double scroll equation, in order to analyze the quite different dynamics of the dual double scroll equation. Two new uses of the Poincaré half-maps are presented: they are used to locate the boundaries between the return/transfer/escape regions and to detect a period-one limit cycle. The Poincaré half-map technique is also used to detect homoclinic and heteroclinic orbits and to locate the region in parameter space for which stable attracting sets exist. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A quartz crystal oscillator with current controlled frequency trimming

    Page(s): 1132 - 1133
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (240 KB)  

    A quartz crystal oscillator circuit is presented whose frequency may be varied by a control current, avoiding the need for a variable-capacitance diode. Experiment results are presented showing frequency versus control current linearity and temperature effects. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design techniques for switched-capacitor broad-band phase-splitting networks

    Page(s): 1096 - 1102
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB)  

    A phase-splitting network is another type of circuit that is suitable to be integrated using the switched-capacitor (SC) technique. However, using existing all-pass SC configurations to realize such networks results in excessive capacitance spread because phase-splitting networks have very low real poles under a wide signal frequency band. Simple analytical expressions derived in this paper show that combining first-order sections of such networks into low-Qbiquads does not reduce the capacitance spread unless the dynamic range of the filter can be sacrificed. A new biquad configuration is proposed for capacitor area efficient realization of low pole all-pass filters. The biquad combines aT-cell with a conventional integrator. TheT-cell integrator realizes the low pole with a product of two capacitance ratios instead of a single capacitance ratio to reduce the capacitance spread. A simple and systematic design procedure is presented for the determination of capacitance values as a function of the poles to be realized. The design procedure achieves minimum total capacitance and equal dynamic range for all amplifiers simultaneously. Commonly performed rescaling of capacitance values after computer simulation is not necessary. The new biquad attenuates offset and flicker noise. However, finite amplifier dc gain and white noise have greater influence on the filter performance. Analytical expressions for transfer function deviations are derived which indicate the amplifier dc gain necessary for a givenomega_0tolerance. Computer simulations show that the total integrated noise of theT-cell biquad only slightly increases compared to that of the conventional biquad realizing the same function. A design example is given which illustrates the design procedure. Compared to the realization of the same transfer function with conventional biquads,T-cell realization reduces the total capacitor area by almost a factor of 20. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An interactive net connectivity check strategy

    Page(s): 1135 - 1137
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB)  

    This letter describes a good strategy for interactive net connectivity checking of IC layout design. A forbidden matrix with three special element values is developed to represent the interconnection status. Two basic operations of this matrix are defined. Using this matrix, the user can quickly know whether the adding connections correspond to the connectivity of the original circuit diagram. Therefore, interactive net connectivity checking can be easily performed during integrated circuit layout design. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.