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No 1 (2017)
5-12 296
Abstract
Questions of the implantation fluency of Si(111) by phosphorus ions influence, the effect of post-implant annealing of Si implantation and an annealing of Mo-Si system and of irradiation by phosphorus ions of generated ohmic contact of system Mo-Si and an annealing at low temperatures on the structure and phase composition of transitional layer have been considered.
13-18 1389
Abstract
The results of the reserch of possibilities of using brushless motors in the stabilization systems of scanning antennas onboard millimeter wave radar are given. For this purpose, peculiarities of change of momentary motor shaft speed for various values of acceleration have been studied in the course of experimental studies, as well as a comparison of the possible operating modes have been complited. The reserch was carried out with engines MAXON EC-max-2 .
19-25 332
Abstract
The article reviews radar operation mode where the absence of radar targets at the direction of probing pulse emission is determined in one period of pulse with high probability of PCDF (correct detection failure). Operation of the digital receiving device is based upon a nonparametric detector that provides statistical processing of input mix of noise and regular signal, if the latter is available. It allows to get the high indicators for continuous wave emission or simple radio-pulse emission for one probing period of pulse emission when signal and noise are already equal. The technique provides for expedite consequential space scan due to adjustment of probing time for a single angular direction and retaining space scanning beam depending on target environment within radar scanning zone.
26-33 405
Abstract
Comparison between two common spatial combining algorithms, namely, optimal combining (OC) and maximal ratio combining (MRC) is carried out based on definition of a gain ratio. The receive carrier-to-interference plus noise ratio (CINR) is applied in Raleigh fading wireless communication systems to define the gain CINROC/CINRMRC with multiple interferences when the generalized approach to signal processing in noise is employed. The exact expression for the probability density function (pdf) and analytical solution for the average gain CINROC/CINRMRC in the case of a single interference is derived. For multiple interferences Monte-Carlo simulation to define the pdf and gain CINROC/CINRMRC is used. Additionally, an upper bound to the gain CINROC/CINRMRC to determine when the OC will exhibit significant gains over MRC is derived.
34-41 441
Abstract
An analysis of computational pipelines and their optimization methods has been performed. A class of dataflow pipelines that do not use resource sharing and obtain high throughput has been considered. Pipeline optimization tasks being solved during high-level synthesis from random logic behavioral specifications in programming and hardware description languages have been considered. A heuristic genetic optimization algorithm which is capable of handling large designs has been proposed and investigated.
42-49 1422
Abstract
The results of estimation of required and sufficient levels of radiated power of base stations of cellular communications of GSM standard at the voice communication mode on urban area, taking into account average attenuation of radio waves in buildings and levels of intranetwork interference are given. The analysis is made on the basis of behavior simulation of the fragment of cellular network, executed with the use of multibeam radiowave propagation model and the topological model of a fragment of urban area of the central part of Minsk by comparison of quantiles of statistical distributions of levels of received signals on various floors of buildings and also relative quantity of mobile stations, for which «Signal / (Interference + Noise)» ratio does not exceed a critical threshold of 9 dB, on various floors of buildings at different radiation power of base station. In the modeled urban area of medium number of building storeys the high communication quality is achieved at base station of GSM-1800 networks equivalent isotropic radiated power 43-45 dBm, and is provided by improvement of intrasystem EMC of cellular network at the expense of increase of cluster dimensionality of frequency sharing. Increase of base station radiation power greater than 45 dBm does not lead to improvement of communication quality, but impairs electromagnetic ecology of urban areas.
50-57 347
Abstract
A technique of calculation conditional probability of a correct signals identification and examples of its calculations for concrete situational are presented. The comparative analysis of reliability of signal-parametrical, existential and complex identification algorithms is lead.
58-64 375
Abstract
A method to manage reliability of software is proposed in this paper. The method is based on fast forecasting of software reliability and monitoring of reliability changes through time. Reliability forecast is given by building correlation between known issues in software and subcharacteristics of reliability. Changes of relibility are monitored with exponentially weighted moving average charts.
65-70 1386
Abstract
There are proposed run-length encoding algorithms to compress grayscale images lossless and loosy compression taking into account the likelihood of the occurrence of pixel values and providing thereby increasing the compression ratio.
71-76 273
Abstract
The results of investigation of thermal effects in the water-containing composites by differential thermal analysis are presented. The dependence of the thermal phase transition points of the first and the second kind from the structure basis and type of mortar filler has been established. The possibility of a more detailed expansion of the temperature operating range of water-containing materials as electromagnetic radiation screens via shape of the DTA curve analysis is justified.
77-81 345
Abstract
The problem of increasing the speed of the encryption algorithms for their hardware implementation using parallel processing of algorithms fragments is considered. The results of analysis and simulation of hardware implementation of the three encryption algorithms with varying degrees of parallelism are given. The efficiency of parallelization algorithms operations is estimated.
82-86 1442
Abstract
Six variants of mathematical models of authentification during users work with mobile applications in cloud area are represented: with application server, with applications forms, on sertification, with one-time parol, on accesses keys, and with tokens. Three factors simbol description for authentification classification for chois thear models is given. The three level seven factor approuch to identificators classification for model identification is given. The intelligence approach for choice of identification and authentification system (IAS) on the base of expert system (ES) knowledge base roles is proposed. The model of decision support system in ES may be based as on expert approach such as on automatic regime of server.
87-90 2846
Abstract
The results of the study of electromagnetic characteristics of the carbon-containing non-woven fabric with geometric irregularities in the frequency range 0.7…17 GHz are presented.


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ISSN 1729-7648 (Print)
ISSN 2708-0382 (Online)