By Topic

Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on

Issue 8 • Date Aug 1994

Filter Results

Displaying Results 1 - 8 of 8
  • On the use of chaos to reduce idle-channel tones in delta-sigma modulators

    Publication Year: 1994 , Page(s): 539 - 547
    Cited by:  Papers (25)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (967 KB)  

    Delta-sigma modulators are popular circuits for constructing high precision analog-to-digital and digital-to-analog converters. These systems contain a single nonlinear element (a quantizer) embedded in an otherwise linear system, and can exhibit such nonlinear behavior as limit cycles, subharmonics, phase-locking and chaos. Due to the discrete spectra that result when limit cycles are present, human listeners perceive objectionable tones in the quantization noise. This problem can be overcome by using dither or, as this paper suggests, by making the modulator chaotic. The effectiveness of the technique is illustrated and its impact on modulator complexity, stability, and performance is discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Real-time computation of the eigenvector corresponding to the smallest eigenvalue of a positive definite matrix

    Publication Year: 1994 , Page(s): 550 - 553
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (406 KB)  

    In the real-time applications of many signal processing algorithms, such as the TLS (Total Least Squares) algorithm, it is desired to compute as fast as possible the eigenvector corresponding to the smallest eigenvalue of a positive definite matrix. This paper proposes an analog circuit approach to computing in real-time the desired eigenvector. We show analytically and by simulations that the proposed circuit is guaranteed to be stable and to provide the results arbitrarily close to the accurate eigenvector within an elapsed time of only a few characteristic time constants of the circuit. View full abstract»

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

    Publication Year: 1994 , Page(s): 557 - 558
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (223 KB)  

    This correspondence presents the results of an investigation into capacitive ladder networks. It was found that capacitive ladder networks can be extended to higher order structures by a replacement process. The input capacitance for all ladder networks and their extensions is proportional to a ratio of Fibonacci numbers and an iterative parameter. Examples of higher order networks are included. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Accurate transient simulation algorithm for high-speed interconnections

    Publication Year: 1994 , Page(s): 548 - 550
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (364 KB)  

    In this letter, we present a new accurate transient simulation algorithm for high-speed interconnection structures consisting of general uniform dispersive and lossy multiconductor transmission lines terminated in arbitrary loads. All ports of the interconnection structure are modeled as extended Thevenin models. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • McClellan transform based design techniques for two-dimensional linear-phase FIR filters

    Publication Year: 1994 , Page(s): 505 - 517
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1254 KB)  

    This paper considers the design problem of two-dimensional (2-D) linear-phase FIR digital filters through the use of the McClellan transform method. We present two methods for determining the coefficients of the McClellan transform when designing 2-D linear-phase FIR digital filters with continuous and powers-of-two coefficients, respectively. Based on the proposed methods, the contour approximation for 1-D (one-dimensional) to 2-D digital filter transformation and finding the band-edge frequencies of the corresponding 1-D FIR digital filter can be achieved simultaneously. This results in that the required complexity of the designed 2-D digital filter satisfying the design specifications can be minimized. Moreover, the proposed methods allow us to employ the McClellan transform with order more than one for enhancing the capability of the original McClellan transform. Considering the determination of the McClellan transform coefficients and the band-edge frequencies for the design, we formulate the design problem as a linear programming optimization problem. Then, an efficient design procedure is presented to avoid the use of time consuming simplex algorithms. For the powers-of-two coefficient design, a discrete design procedure is presented to avoid the use of time-consuming mixed integer linear programming algorithms. Computer simulations for showing the effectiveness of the proposed design techniques are also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel algorithm for DC analysis of piecewise-linear circuits: popcorn

    Publication Year: 1994 , Page(s): 553 - 556
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (485 KB)  

    A fast and convergent iteration method for piecewise-linear analysis of nonlinear resistive circuits is presented. Most of the existing algorithms are applicable only to a limited class of circuits. In general, they are either not convergent or too slow for large circuits. The new algorithm presented in the paper is much more efficient than the existing ones and can be applied to any piecewise-linear circuit. It is based on the piecewise-linear version of the Newton-Raphson algorithm. As opposed to the Newton-Raphson method, the new algorithm is globally convergent from an arbitrary starting point. It is simple to understand and it can be easily programmed. Some numerical examples are given in order to demonstrate the effectiveness of the proposed algorithm in terms of the amount of computation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stability of cellular neural networks and delayed cellular neural networks with nonpositive templates and nonmonotonic output functions

    Publication Year: 1994 , Page(s): 518 - 528
    Cited by:  Papers (44)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (894 KB)  

    In this paper the problem of the stability of Cellular Neural Networks (CNN's) and Delayed Cellular Neural Networks (DCNN's) is addressed by means of Lyapunov functions (functionals in the delayed case); new classes of nonpositive templates, describing CNN's and DCNN's, are shown to be stable and some conditions are found ensuring the complete stability of dominant template DCNN's and CNN's with nonmonotonic output functions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Qualitative classification of the dynamics of a class of adaptive feedback systems

    Publication Year: 1994 , Page(s): 529 - 538
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (961 KB)  

    In this paper we consider a class adaptive feedback systems of arbitrary order with unmodeled dynamics and constant disturbances. We demonstrate that the dynamical behavior of any system in this class must conform to a limited number of options varying according to the selection of system parameters such as the leakage constant and the adaptation step-size. Our main tool is bifurcation analysis, which describes in a qualitative fashion how the stability properties of a dynamical system may alter as a parameter is varied. The importance of the results presented in this paper is that they permit the generation of adaptation leakage tuning rules akin to those for setting controller gains in process control. View full abstract»

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