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IEEE Transactions on Information Theory

Volume 14 Issue 1 • January 1968

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Displaying Results 1 - 25 of 42
  • Information transmission in evolution

    Publication Year: 1968, Page(s):3 - 6
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (499 KB)

    On the basis of a model previously established for the random-mutation portion of the synthetic theory of evolution, an investigation is made of the information that can be transmitted from the environment to the evolving species. The probability that a given adaptive character is produced decreases with increasing information measure of the adaptive character. The average information transmitted ... View full abstract»

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  • An extension of rate-distortion theory to confusion matrices

    Publication Year: 1968, Page(s):6 - 11
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (808 KB)

    A discrete confusion matrix is completely specified by a set of transition probabilities,<tex>P_{D}(y/x)</tex>, where<tex>x</tex>and<tex>y</tex>are the input and output symbols, respectively. In this paper we examine the possibility of simulating such a matrix by an available channel with processors at the input and output, when the source is specified beforehan... View full abstract»

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  • On a class of processes arising in linear estimation theory

    Publication Year: 1968, Page(s):12 - 16
    Cited by:  Papers (35)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (724 KB)

    This paper considers a class of stochastic processes, called {\em spherically invariant},which have the property that all mean-square estimation problems on them have linear solutions. It is shown that their multivariate characteristic functions are univariate functions of a quadratic form. The corresponding densities are easily found by means of the Hankel transform. Relations between spherical i... View full abstract»

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  • On optimal and suboptimal nonlinear filters for discrete inputs

    Publication Year: 1968, Page(s):16 - 21
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (788 KB)

    The determination of minimum-mean-squared-error (MMSE) nonlinear filters usually involves formidable mathematical difficulties. These difficulties may be bypassed by restricting attention to special classes of filters or special processes. One such class is Zadeh's class<tex>n_{1}</tex>, which for the general case also involves mathematical difficulties. In this work two realizations o... View full abstract»

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  • The signalimessignal, noiseimesnoise, and signalimesnoise output of a nonlinearity

    Publication Year: 1968, Page(s):21 - 27
    Cited by:  Papers (45)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (889 KB)

    The signal\timessignal, noise\timesnoise, and signal\timesnoise output components of a nonlinearity are defined in a manner agreeing with intuition. The definitions are shown to accord with previous usage, for which they now provide a clear meaning. The case of a limiter is used as an illustrative example. The approach is applicable not only to fixed memoryless tra... View full abstract»

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  • The amount of information that y gives about X

    Publication Year: 1968, Page(s):27 - 31
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (640 KB)

    No single measure<tex>M(X;y)</tex>of the amount of information that a specific value<tex>y</tex>of a random variable<tex>Y</tex>gives about another random variable<tex>X</tex>has all of the desirable properties possessed by Shannon's measure<tex>I(X;Y) = E\{M(X;y)\}</tex>of the average mutual information of<tex>X</tex>and<t... View full abstract»

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  • Quantum electrodynamics of a communication channel

    Publication Year: 1968, Page(s):32 - 37
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (979 KB)

    A simple one-dimensional model is taken to illustrate the quantum effects of a narrowband communication system. The system is quantized, and its dynamics are discussed in terms of the Heisenberg equations for field operators. The detection process of a "coherent joint detector," whose compatibility with quantum physics was justified elsewhere, is discussed. The detector, which is capable of measur... View full abstract»

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  • Optimum linear transmission of analog data for channels with feedback

    Publication Year: 1968, Page(s):38 - 43
    Cited by:  Papers (30)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (850 KB)

    With feedback, the transmission of analog data over a channel can be regarded as a stochastic-control problem. Restricting ourselves to linear receiver operations and an average power constraint, we take this approach to find minimum mean-square error signals for multiplicative and additive noise channels with noiseless feedback and for additive noise channels with noisy feedback. Our solution for... View full abstract»

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  • The effect of attenuation on the capacity of a photon channel

    Publication Year: 1968, Page(s):44 - 50
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1015 KB)

    The process of attenuation of electromagnetic energy when transmitted over some communication channel is stochastic in nature. Hence one can expect that, since equivocation is imposed in the transmission, in addition to reduction of average signal power, there will be a consequent degradation in channel capacity. We have attempted to calculate the effect of this phenomenon on an otherwise noiseles... View full abstract»

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  • Estimation by the nearest neighbor rule

    Publication Year: 1968, Page(s):50 - 55
    Cited by:  Papers (60)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (877 KB)

    Let<tex>R^{\ast}</tex>denote the Bayes risk (minimum expected loss) for the problem of estimating<tex>\theta \varepsilon \Theta</tex>, given an observed random variable<tex>x</tex>, joint probability distribution<tex>F(x,\theta)</tex>, and loss function<tex>L</tex>. Consider the problem in which the only knowledge of<tex>F</tex&g... View full abstract»

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  • On the mean accuracy of statistical pattern recognizers

    Publication Year: 1968, Page(s):55 - 63
    Cited by:  Papers (732)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1437 KB)

    The overall mean recognition probability (mean accuracy) of a pattern classifier is calculated and numerically plotted as a function of the pattern measurement complexity n and design data set size<tex>m</tex>. Utilized is the well-known probabilistic model of a two-class, discrete-measurement pattern environment (no Gaussian or statistical independence assumptions are made). The minim... View full abstract»

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  • Studies of sequential detection systems with uncertainty feedback

    Publication Year: 1968, Page(s):63 - 70
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1111 KB)

    The problem studied is the design of signals in a binary sequential detection system which has a feedback channel available to it. Until a decision is made on a particular transmission, the transmitter is informed via the feedback channel of the state of uncertainty at the receiver. This uncertainty feedback modulates the transmitted signal so that, for a prescribed probability of error, the avera... View full abstract»

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  • Retransmission schemes for communication systems with applications to group codes

    Publication Year: 1968, Page(s):71 - 77
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1176 KB)

    Communication systems are considered in which there exists an auxiliary channel over which the receiver can make requests for retransmission. In general, it is assumed that the auxiliary channel is noiseless and the main channel is discrete and memoryless. It is also assumed that the a priori probabilities of the message symbols are known. A sequential receiver strategy is introduced which at each... View full abstract»

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  • Some criteria for frequency domain design of signals imbedded in Gaussian noise

    Publication Year: 1968, Page(s):78 - 82
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (627 KB)

    The design of time-limited binary signals imbedded in colored Gaussian noise resulting from passing white noise through a channel of known transfer function is investigated. It is shown that, for a class of channels whose magnitude characteristic is expressible as the ratio of polynomials with the numerator divisible by and of lower or the same degree as the denominator, the output noise kernel (c... View full abstract»

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  • A linear decomposition of stationary random processes into uncorrelated and completely correlated components

    Publication Year: 1968, Page(s):83 - 88
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (885 KB)

    This paper deals with a decomposition of a set of stationary random processes:<tex>x_{1}, x_{2}, \cdots, x_{n}</tex>. The decomposition has the form:<tex>x_{1} = y_{11}, x_{2} = y_{21} + y_{22}, x_{3} = y_{31} + y_{32} + y_{33}</tex>, etc., where the components<tex>y_{ij}</tex>have the following properties: for a fixed<tex>i</tex>, they are completel... View full abstract»

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  • Influence of bandwidth on some nonlinear transformations of a Gaussian random process

    Publication Year: 1968, Page(s):88 - 93
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (851 KB)

    Predictions of the response probability density function for bandlimited white noise excitation of nonlinear systems often employ the so-called Fokker-Planck technique. While these predictions are exact for white noise, there exist no general criteria for assessing their accuracy in physical situations. This paper endeavors to shed some light on the problem and perhaps point the way toward better ... View full abstract»

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  • The state-variable approach to analog communication theory

    Publication Year: 1968, Page(s):94 - 104
    Cited by:  Papers (16)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1706 KB)

    A new approach is presented for estimating stochastic signals. The approach is based on the use of Markov processes and state-variable concepts. Equations are presented for approximate minimum mean-square error estimates of a Markovian state vector observed in a signal in which it is imbedded nonlinearly. A general model for analog communication via randomly time-varying channels is given and rela... View full abstract»

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  • A comparison of average-likelihood and maximum-likelihood ratio tests for detecting radar targets of unknown Doppler frequency

    Publication Year: 1968, Page(s):104 - 110
    Cited by:  Papers (23)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (790 KB)

    In a coherent search rader, the pulse-to-pulse Doppler shift of a signal is generally not known a priori. Given the distribution of this parameter, the best test variable for detection is the average of the likelihood ratio with respect to target Doppler frequency. Most coherent search radars employ a maximum-likelihood ratio detector, that is, a bank of independent Doppler filters, for detection.... View full abstract»

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  • Elliptically symmetric distributions

    Publication Year: 1968, Page(s):110 - 120
    Cited by:  Papers (20)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1708 KB)

    Elliptically symmetric distributions are second-order distributions with probability densities whose contours of equal height are ellipses. This class includes the Gaussian and sine-wave distributions and others which can be generated from certain first-order distributions. Members of this class have several desirable features for the description of the second-order statistics of the transformatio... View full abstract»

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  • Error propagation and definite decoding of convolutional codes

    Publication Year: 1968, Page(s):121 - 128
    Cited by:  Papers (22)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1218 KB)

    The error-propagation effect in decoding convolutional codes is a result of the internal feedback in the usual decoding method, feedback decoding (FD). As a measure of this effect, the propagation length<tex>L</tex>of a system is defined as the maximum span of decoding errors following a decoding error when all succeding parity checks are satisfied. A relationship between<tex>L&l... View full abstract»

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  • On the Schalkwijk-Kailath coding scheme with a peak energy constraint

    Publication Year: 1968, Page(s):129 - 134
    Cited by:  Papers (32)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (770 KB)

    In a recent series of papers, [2]-[4] Schalkwijk and Kailath have proposed a block coding scheme for transmission over the additive white Gaussian noise channel with one-sided spectral density<tex>N_{0}</tex>using a noiseless delayless feedback link. The signals have bandwidth<tex>W (W \leq \infty)</tex>and average power<tex>\bar{P}</tex>. They show how to commu... View full abstract»

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  • Error-correcting codes for a compound channel

    Publication Year: 1968, Page(s):135 - 139
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (744 KB)

    Many data-transmission and data-storage systems are corrupted by disturbances of both the burst type and the random type. In this paper two classes of error-correcting codes for use with these systems have been constructed analytically and with the aid of a computer. Although not optimal, these codes do have the advantage of ease of implementation, View full abstract»

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  • Minimax combinational coding

    Publication Year: 1968, Page(s):139 - 150
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1842 KB)

    This paper treats the problem of compressing binary strings of fixed length into shorter strings of fixed length. Constraints are assumed with respect to the maximum number of ones which can occur in the input binary string and on the memory available for encoding or decoding using table look-up operations. Bounds and coding techniques are presented. There appear to be many applications to the inf... View full abstract»

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  • On trinomial recurrences

    Publication Year: 1968, Page(s):150 - 151
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (217 KB)

    Let<tex>G</tex>be the set of all linear recurring sequences generated by a polynomial<tex>f</tex>. It is shown that the linear functional advancing the phase of every sequence in<tex>G</tex>by<tex>k</tex>may be obtained essentially as the<tex>k</tex>th state of a certain member of<tex>G</tex>depending only on<tex>f</t... View full abstract»

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  • Statistical music analysis: An objection to Fucks' curtosis curve (Corresp.)

    Publication Year: 1968, Page(s):152 - 153
    Request permission for commercial reuse | PDF file iconPDF (315 KB)
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Aims & Scope

IEEE Transactions on Information Theory publishes papers concerned with the transmission, processing, and utilization of information.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Alexander Barg

Department of Electrical and Computer Engineering and the Institute for Systems Research, University of Maryland

email: abarg-ittrans@ece.umd.edu