A translation of Problemy Peredachi Informatsii

Volume 19, Number 3, July–September, 1983
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Performance of $q$-ary Coding in Channels with Fading When Multiple-Frequency Signals Are Used
V. I. Korzhik and N. A. Savel'ev
pp. 177–183

Abstract—The authors investigate the upper bound for the erroneous-decoding probabilities in $q$-ary channels made up of multiple-frequency modems with independent frequency fading. The error distributions with respect to time that are least favorable for encoding are determined, as well as the capacity of $q$-ary channels and the energy gain from the use of encoding for Rayleigh fading.


Coding in an Asynchronous Multiple-Access Channel
G. Sh. Poltyrev
pp. 184–191

Abstract—The capacity region for a discrete memoryless channel with asynchronous multiple access is determined. An upper bound is established for the decoding-error probability for lattice codes in the case of Viterbi-algorithm decoding in discrete memoryless channels with synchronous and asynchronous multiple access.


Constructive Models of Random Sequences with Specified Statistical Properties and Their Application
N. N. Evtikhiev and E. A. Sandler
pp. 192–196

Abstract—The authors set up constructive models of stationary ergodic random sequences with specified finite-dimensional probability distributions, which provide, in particular, a representation of random sequences with specified one-dimensional distributions and autocorrelation functions. These models are described by piecewise-linear recursive relations that are easy to implement on computers. Problems of using the models for solving problems dealing with information transmission systems are discussed.


Minimum-Check-Density Codes for Correcting Bytes of Errors, Erasures, or Defects
G. V. Zaitsev, V. A. Zinov'ev, and N. V. Semakov
pp. 197–204

Abstract—The authors propose a new class of codes with minimum redundancy and minimum check density that correct errors, defects, or erasures of byte type. The decoding devices for these codes are simple and have a uniform structure.


Some Aspects of Estimation of the Bispectral Density of a Stationary Stochastic Process
V. G. Alekseev
pp. 204–214

Abstract—Statistical properties of estimates of the bispectral density of a stationary stochastic process are investigated. It is shown that the mean square of the modulus of the bispectral density estimation error depends significantly on the degree of smoothness of its real and imaginary parts. A method of estimating the bispectral density when there are systematic gaps in observations is also indicated.


Entropy Characteristics and Linear Approximations for a Homogeneous Gaussian Field
M. S. Pinsker and L. B. Sofman
pp. 214–226

Abstract—The concepts of $\varepsilon,\delta$-entropy, $\varepsilon,\delta$-dimension, and $n,\delta$-width of a random field are introduced. The asymptotic forms of these quantities are calculated for a homogeneous Gaussian field specified on an expanding system of sets in $\mathbb{R}^n$.


On Selection of Features in Pattern Recognition
G. P. Tartakovskii and N. A. Ivanchuk
pp. 227–234

Abstract—For the case of complete a priori information, a procedure is found for selecting a combination of independent features in two formulations. In the first formulation, the minimum number of features ensures a specified risk level in pattern recognition; in the second formulation, the average risk is minimized by selecting an array of features, with allowance for the cost of obtaining and of processing the features. An example of feature selection is given for the case of two-alternative recognition.


Capabilities of Automata upon Traversing a Plane
A. V. Andzhan
pp. 235–244

Abstract—The article examines the traversal of a two-dimensional square grid by finite systems of automata equipped with counters, stacks, and so forth. The author determines which types of systems can traverse the entire grid, and which cannot. The characteristics of those regions of the grid that can be traversed by systems not capable of traversing the entire grid are obtained.


On Some Markov Queuing Networks with Absolute Priorities
M. Ya. Postan
pp. 244–252

Abstract—The article examines open and closed Markov queuing networks with several priority classes of requests, absolute priorities, and an arbitrary number of multichannel nodes. Expressions are obtained in explicit form for the stationary expected values of the numbers of requests of different classes at the nodes, and some priority optimization problems in networks are solved.


(available in Russian only)


New Binary Codes with Minimum Distance 3
A. M. Romanov
pp. 101–102 (Russian issue)

Abstract—There exists a binary code of length 16 with minimum distance 3 between codewords, which contains more codewords than the code constructed by Sloane and Whitehead.


Arithmetic $(n,A)$-Codes Dual to Iterative Codes
I. M. Boyarinov
pp. 102–106 (Russian issue)

Abstract—Arithmetic cyclic $(n,A)$-codes dual to iterative codes and their subcodes are considered. We determine the minimum distance and describe a majority decoding algorithm for these codes.


On Some Features of Linear Cyclic Codes
I. E. Shparlinsky
pp. 106–110 (Russian issue)

Abstract—We obtain lower bounds for the code distance of a linear cyclic code with an irreducible check polynomial and a new upper bound for correlation functions (both periodic and aperiodic) of two arbitrary $m$-sequences. Also, we construct an infinite family of linear cyclic codes with better parameters than those of BCH codes.


OBITUARY. Vadim Nikolaevich Roginsky
p. 111 (Russian issue)