PROBLEMS OF INFORMATION TRANSMISSION
A translation of Problemy Peredachi Informatsii


Volume 2, Number 1, January–March, 1966
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Academician Aleksandr Aleksandrovich Kharkevich
E. L. Blokh, A. Yu. Ishlinskii, I. A. Ovseevich, and B. N. Petrov
pp. 1–9

 

On the Asymptotic Behavior of the Transmission Capacity of Some Communication Channels
V. V. Prelov
pp. 10–21

Abstract—It is known that determining the transmission capacity of communication channels is an important and difficult problem leading, even in the simplest cases, to a system of transcendental equations which cannot be solved explicitly. In this paper asymptotic formulas are found for the transmission capacities of some communication channels.

 

Asynchronous Channels with Synchrosymbols
B. S. Tsybakov
pp. 22–28

Abstract—In certain discrete channels, failure to maintain synchronization causes the length of output blocks to be a random variable. This paper considers one such channel in which synchrosymbols are received without errors. For this channel the class of nonuniform codes formed of blocks containing the same number of synchrosymbols is determined. The largest rate with which information can be transmitted with these codes and still yield an arbitrarily small error or probability is ascertained. Examples are given.

 

Shadows of Fuzzy Sets
L. A. Zadeh
pp. 29–34

Abstract—The shadow of a fuzzy set is defined as the result of projecting it onto a hyperplane. It is shown that under such projections the properties of convexity and concavity are invariant and the degree of separability of two fuzzy sets is not increased. The notion of a bound of a fuzzy set is introduced, which is useful when a set has to be estimated from the knowledge of its shadows.

 

The Transmission Rate for Certain Quantum Communications Channels
R. L. Stratonovich
pp. 35–44

Abstract—The author considers a block diagram for a quantum communications channel consisting of both classical and specifically quantum elements. The way in which the density matrix is transformed in the transmission line under the influence of attenuation and additive noise is examined. The conditional probabilities $w(r\,|\,s)$ formed in the receiver as a result of quantum measurement of $r$ are determined. For two particular forms of modulation-amplitude modulation and coherent modulation-and the corresponding methods of reception, the author computes the information capacity for fixed signal power at the channel input in the presence of thermal noise. Coherent modulation is found to have advantages over amplitude modulation.

 

On the Signal/Noise Ratio for a Channel with Additive Thermal Noise
V. L. Stefanyuk
pp. 45–52

Abstract—A formalism for the understanding of additive thermal noise is presented which permits the construction of a quantum-mechanical picture of the additive interaction of signal and thermal noise. Under the assumption that the transmitter sends signals in such a way as to minimize the power losses related to the uncertainty principle, while the signals differ only in their mean values, probability distributions for various physical quantities in the presence of signals are presented. For a given mean signal power the best signal$/$noise ratio is found. In this connection irreversible changes, caused by the quantum system of measurement, are taken into account, and physical measurement is indicated which, with the use of “sinusoidal” signals, realizes the best signal$/$noise ratio.

 

Simulation of a Self-Reproducing System on a Universal Automaton
Yu. P. Ofman
pp. 53–56

Abstract—A universal automaton consisting of $n\log^2n$ stages (in succession) is described. Any self-reproducing automaton not consisting of more than $n$ stages can be simulated on it.

 

Classification of Switching Functions in the Synthesis of Majority-Element Circuits
N. N. Nemshilov
pp. 57–62

Abstract—The author considers certain properties of majority-element combinational circuits that realize self-dual switching functions. A classification of self-dual functions that facilitates synthesis of majority-element circuits is proposed.

 

The Determination of Correlation Properties of Discrete Communication Signals at the Output of a Communication Channel with Random Variation of Parameters
A. S. Kotousov
pp. 63–69

Abstract—The author investigates problems of determining the correlation properties of a radiotelegraph signal at the output of a communication channel with variable parameters. As an example, the signal autocorrelation function and power spectrum are computed for a synchronous frequency-telegraphy system.

 

The Correlation Between the Properties of a Binary Group Code and Those of its Null Space
V. I. Korzhik
pp. 70–74

Abstract—A new proof is given of a theorem on the linear dependence of the distribution of the weights of a code and of its null space. The connection is determined between the number of blocks of any length belonging to the code and some properties of its null space. A structural property of cyclic codes is found as a corollary.

 

Asymptotic Behavior of the Maximum of the Weight of a Finite Tree
V. S. Grinberg and A. D. Korshunov
pp. 75–78

Abstract—The results obtained by B.A. Trakhtenbrot [Sib. Mat. Zhurn., 1964, vol. 5, no. 1, pp. 186–191] are improved.

 

Transformation of the Time Parameters of Signals in Discrete Asynchronous Automata
V. N. Roginskii
pp. 79–82

Abstract—The author considers the basic devices that change signal duration in asynchronous automata: delays, filters, differentiators, pulse shapers, and memory elements. The properties of these devices and models of them are considered.

 

Algorithm Determining the Maximum of a Logical Function
V. F. D'yachenko
pp. 83–85

Abstract—The maximum of a logical function over all possible combinations of values of logical variables of a certain subset is defined, and an algorithm for obtaining it without sorting through all the values is described. Equivalent relations between a logical function and its maximum which facilitate the transformation of such functions are given. There is an example of the use of the algorithm.

 

Remark on Increased Network Reliability Using Varying Dependence of Values of a Boolean Function on the Different Arguments
Sh. E. Bozoyan
pp. 86–88

Abstract—Some aspects of the sensitivity of functions of logical algebra to changes in the separate arguments or groups of arguments are considered. The concept of the activity of a group of arguments of such a function is introduced in an obvious way. A method of increasing the reliability of networks, based on the varying dependence of the values of the function on the values of different arguments, is described.