IEEE Transactions on Information Theory

Volume 35 Issue 5 • Sept. 1989

Filter Results

Displaying Results 1 - 25 of 29
  • Distributed Bayesian signal detection

    Publication Year: 1989, Page(s):995 - 1000
    Cited by:  Papers (139)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (459 KB)

    The signal detection problem is considered for the case in which distributed sensors are used and a global decision is desired. Local decisions from the sensors are fed to a data fusion center, which yields a global decision based on a fusion rule. A Bayesian formulation of the problem is considered, and a person-by-person optimization of the overall system is carried out. The special case of iden... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A minimum discrimination information approach for hidden Markov modeling

    Publication Year: 1989, Page(s):1001 - 1013
    Cited by:  Papers (41)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1254 KB)

    An iterative approach for minimum-discrimination-information (MDI) hidden Markov modeling of information sources is proposed. The approach is developed for sources characterized by a given set of partial covariance matrices and for hidden Markov models (HMMs) with Gaussian autoregressive output probability distributions (PDs). The approach aims at estimating the HMM which yields the MDI with respe... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the estimation of the order of a Markov chain and universal data compression

    Publication Year: 1989, Page(s):1014 - 1019
    Cited by:  Papers (76)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (543 KB)

    The authors estimate the order of a finite Markov source based on empirically observed statistics. The performance criterion adopted is to minimize the probability of underestimating the model order while keeping the overestimation probability exponent at a prescribed level. A universal asymptotically optimal test, in the sense just defined, is proposed for the case where a given integer is known ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Coset codes for partial response channels; or, coset codes with spectral nulls

    Publication Year: 1989, Page(s):925 - 943
    Cited by:  Papers (68)  |  Patents (28)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (2169 KB)

    Known coset codes are adapted for use on partial response channels or to generate signals with spectral nulls. By using coset precoding and running digital sum feedback, any desired tradeoff can be achieved between the power and spectra of the relevant sequences, up to the optimum tradeoff possible. A fundamental theorem specifying this optimum tradeoff is given. A maximum-likelihood-sequence-esti... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Limited search trellis decoding of convolutional codes

    Publication Year: 1989, Page(s):944 - 955
    Cited by:  Papers (89)  |  Patents (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1080 KB)

    The least storage and node computation required by a breadth-first tree or trellis decoder that corrects t errors over the binary symmetric channels is calculated. Breadth-first decoders work with code paths of the same length, without backtracking. The Viterbi algorithm is an exhaustive trellis decoder of this type; other schemes look at a subset of the tree or trellis paths. For random tree code... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Information rates for magnetic recording channels with peak- and slope-limited magnetization

    Publication Year: 1989, Page(s):956 - 962
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (580 KB)

    A model for magnetic recording is proposed which uses two parameters to describe the limitations on the remanent magnetization in the medium: the dimensionless peak value A/sub m/ and the steepest slope B(s/sup -1/). A low-pass bandwidth restriction W(s/sup -1/) due to read circuits is also included. Lower and upper bounds on the achievable transmission rates are derived in terms of the signal-to-... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Maximum likelihood soft decoding of binary block codes and decoders for the Golay codes

    Publication Year: 1989, Page(s):963 - 975
    Cited by:  Papers (80)  |  Patents (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1297 KB)

    Maximum-likelihood soft-decision decoding of linear block codes is addressed. A binary multiple-check generalization of the Wagner rule is presented, and two methods for its implementation, one of which resembles the suboptimal Forney-Chase algorithms, are described. Besides efficient soft decoding of small codes, the generalized rule enables utilization of subspaces of a wide variety, thereby yie... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Neural networks, error-correcting codes, and polynomials over the binary n-cube

    Publication Year: 1989, Page(s):976 - 987
    Cited by:  Papers (64)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1076 KB)

    Several ways of relating the concept of error-correcting codes to the concept of neural networks are presented. Performing maximum-likelihood decoding in a linear block error-correcting code is shown to be equivalent to finding a global maximum of the energy function of a certain neural network. Given a linear block code, a neural network can be constructed in such a way that every codeword corres... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An information theoretic approach to the distributed detection problem

    Publication Year: 1989, Page(s):988 - 994
    Cited by:  Papers (47)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (575 KB)

    The distributed detection problem is considered from an information-theoretic point of view. An entropy-based cost function is used for system optimization. This cost function maximizes the amount of information transfer between the input and the output. Distributed detection system topologies with and without a fusion center are considered, and an optimal fusion rule and optimal decision rules ar... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-resolution quantization theory and the vector quantizer advantage

    Publication Year: 1989, Page(s):1020 - 1033
    Cited by:  Papers (122)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1252 KB)

    The authors consider how much performance advantage a fixed-dimensional vector quantizer can gain over a scalar quantizer. They collect several results from high-resolution or asymptotic (in rate) quantization theory and use them to identify source and system characteristics that contribute to the vector quantizer advantage. One well-known advantage is due to improvement in the space-filling prope... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Splitting algorithms in noisy channels with memory

    Publication Year: 1989, Page(s):1034 - 1043
    Cited by:  Papers (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (945 KB)

    Multi-access networks are considered in which the shared channel is noisy. The authors assume a slotted-time collision-type channel, Poisson infinite-user model, and binary feedback. Due to the noise in the shared channel, the received signal may be detected as a collision even though no message or a single message is transmitted. This kind of imperfect feedback is referred to as error. A common a... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Connectivity properties of a packet radio network model

    Publication Year: 1989, Page(s):1044 - 1047
    Cited by:  Papers (155)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (359 KB)

    A model of a packet radio network in which transmitters with range R are distributed according to a two-dimensional Poisson point process with density D is examined. To ensure network connectivity, it is shown that pi R/sup 2/D, the expected number of nearest neighbors of a transmitter, must grow logarithmically with the area of the network. For an infinite area there exists an infinite connected ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the nonexistence of Barker arrays and related matters

    Publication Year: 1989, Page(s):1048 - 1057
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (858 KB)

    Evidence is presented to support the conclusion that there exists only one equivalence class of binary two-dimensional arrays (both dimensions greater than 1) of +1's and -1's with all out-of-phase aperiodic autocorrelation values bounded in magnitude by unity. It is proved that no such array exists when either dimension is an odd prime or when one dimension is an odd integer and the other is twic... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Estimates of performance sensitivity of a stochastic system

    Publication Year: 1989, Page(s):1058 - 1068
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (774 KB)

    Three kinds of estimates of the performance sensitivity of a stochastic system are discussed. The convergence properties of these estimates are investigated. The first estimate, using the time average of the derivative of the performance function calculated along a sample trajectory, is generally preferable when certain conditions hold for the performance function. The variance of the second estim... View full abstract»

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

    Publication Year: 1989, Page(s):1069 - 1072
    Cited by:  Papers (13)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (400 KB)

    One of the simplest optimization problems solved by Ising spin models of neural memory is associative memory retrieval. The authors study deterministic convergence properties of the Hopfield synchronous retrieval algorithm for such models. In this case a memory, stored in the network by an appropriate choice of connections, is retrieved by setting the neural outputs to the binary pattern of the re... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On Gaussian feedback capacity

    Publication Year: 1989, Page(s):1072 - 1076
    Cited by:  Papers (14)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (463 KB)

    M. Pinsker and P. Ebert (Bell Syst. Tech. J., p.1705-1712, Oct.1970) proved that in channels with additive Gaussian noise, feedback at most doubles the capacity. Recently, T. Cover and S. Pombra (ibid., vol.35, no.1, p.37-43, Jan.1989) proved that feedback at most adds half a bit per transmission. Following their approach, the author proves that in the limit as signal power approaches either zero ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Extension of an entropy property for binary input memoryless symmetric channels

    Publication Year: 1989, Page(s):1077 - 1079
    Cited by:  Papers (17)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (314 KB)

    The channel output entropy property introduced by A.D. Wyner and J. Ziv (ibid., vol.IT-19, p.769-762, Nov.1973) for a binary symmetric channel is extended to arbitrary memoryless symmetric channels with binary inputs and discrete or continuous outputs. This yields lower bounds on the achievable information rates of these channels under constrained binary inputs. Using the interpretation of entropy... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Upper bounds on capacity for a constrained Gaussian channel

    Publication Year: 1989, Page(s):1079 - 1084
    Cited by:  Papers (14)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (635 KB)

    A low-pass and a bandpass additive white Gaussian noise channel with a peak-power constraint imposed on otherwise arbitrary input signals are considered. Upper bounds on the capacity of such channels are derived. They are strictly less than the capacity of the channel when the peak-power constrain is removed and replaced by the average-power constraint, for which the Gaussian inputs are optimum. T... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Tight upper bounds on the redundancy of Huffman codes

    Publication Year: 1989, Page(s):1084 - 1091
    Cited by:  Papers (25)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (770 KB)

    Bounds on the redundancy of Huffman codes in terms of the probability p/sub 1/ of the most likely source letter are provided. In particular, upper bounds are presented that are sharper than the bounds given recently by R.G. Gallager (ibid., vol.IT-24, no.6, p.668-74, Nov.1978) and by R.M. Capocelli et al. (ibid., vol. IT-32, no.6, p.854-857, Nov. 1986) for an interval 2/(2/sup l+1/+1)<p/sub 1/&... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On error-correcting balanced codes

    Publication Year: 1989, Page(s):1091 - 1095
    Cited by:  Papers (24)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (556 KB)

    Results are presented on families of balanced binary error-correcting codes that extend those in the literature. The idea is to consider balanced blocks as symbols over an alphabet and to construct error-correcting codes over that alphabet. Encoding and decoding procedures are presented. Several improvements to the general construction are discussed.<<ETX>> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Error detection in a class of decimal codes

    Publication Year: 1989, Page(s):1095 - 1098
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (468 KB)

    Consideration is given to the problem of multiple parity checks for an n-digit number. Each check relates to specific digits, where the probability p of a particular digit being in error is fixed. The author proves that it is best, in the sense of minimizing the probability of an undetected error, to add either one or n parity checks, depending on the value of n and p.<<ETX>> View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Hamming distance preserving mappings and trellis codes with constrained binary symbols

    Publication Year: 1989, Page(s):1098 - 1103
    Cited by:  Papers (24)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (636 KB)

    The transformation of a linear convolutional code into a run-length-constrained or balanced trellis code with the same or larger free distance is investigated. The transformation involves a Hamming-distance-preserving mapping of the set of unconstrained binary symbols of the convolutional code onto a set of suitably constrained symbols. Simple tests to determine if these mappings can exist and a t... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Recursive density estimation under dependence

    Publication Year: 1989, Page(s):1103 - 1108
    Cited by:  Papers (22)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (564 KB)

    Recursive estimators of the density of weakly dependent random variables are studied under certain absolute regularity and strong mixing conditions. Uniform strong consistency of the density estimators is established, and their rates of convergence are obtained. This study is concerned more with the almost sure uniform consistency of a sequence and its rate of convergence than with pointwise conve... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The estimation of the model order in exponential families

    Publication Year: 1989, Page(s):1109 - 1114
    Cited by:  Papers (33)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (551 KB)

    Estimators are sought that achieve high exponential rate of decrease in the underestimation probability while keeping the overestimation probability exponent at a certain prescribed level. It is assumed that a given integer is known to upper-bound the true order. Some examples are given of possible applications of the proposed method in specific order estimation and hypothesis testing problems.<... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Quantum communication with coherent states

    Publication Year: 1989, Page(s):1114 - 1123
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (922 KB)

    Quantum communication is studied under the cutoff-rate criterion for transmission of M coherent states of real amplitude (M=2, . . ., 7). Comparison with other measurement operators of interest, such as the number and the quasi-classical operators, is made. The effect of quantization of the decision level on the cutoff rate is considered.<<ETX>> View full abstract»

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

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