scholarly journals Studying of the scrambling coding sequence performance based on the ninth order primitive polynomial in telecommunication networks of information systems

Connectivity ◽  
2020 ◽  
Vol 145 (3) ◽  
Author(s):  
O. G. Plyushch ◽  
◽  
V. V. Vyshnivskyi ◽  
S. V. Prokopov ◽  
S. M. Ishcheryakov
Keyword(s):  
Information Systems ◽  
Information Transmission ◽  
Quality Indicators ◽  
Noise Immunity ◽  
Telecommunication Networks ◽  
Degree Polynomial ◽  
Coding Sequences ◽  
Coding Sequence ◽  
Primitive Polynomial ◽  
Transmission Quality

Scrambling coding sequences find wide application in telecommunication networks to improve noise immunity and information transmission concealment. There are many different scrambling coding sequences with different autocorrelation properties from which one can be chosen. In the previous paper the authors researched a possibility of using scrambling coding sequences built on the base of the primitive eighth degree polynomial in telecommunication networks of information systems to enhance noise immunity and concealment of information transmission. This sequence, consisting of two hundred and fifty five chips, showed some good performance in terms of information transmission quality indicators. Nevertheless, some of its limitations were also revealed, which are mostly linked to the number of used chips. This paper aims to overcome the problems by proposing to use scrambling coding sequences based on the ninth degree primitive polynomial. The required polynomial was selected and the needed scrambling sequence generated. This scrambling coding sequence includes five hundred and eleven chips. Computer simulation helped to establish that scrambling coding sequence synthesized using this polynomial permits to substantially improve information transmission quality indicators as compared to the case of the scrambling coding sequence based on the eighth degree polynomial. For example, the interfering signal and internal noise to desired signal ratio, for which reception of transmitted bit sequence is still possible, increased by three decibels. It is clearly linked to the doubling of the number of the used chips. To preserve the transmission rate, the occupied frequency spectrum needs to be doubled. An inference is made as to a possibility of using the synthesized coding sequence in practical realizations of telecommunication channels.

scholarly journals Study of scrambling coding sequence utilization in telecommunication networks of information systems

2020 ◽  
Vol 69 (2) ◽  
Author(s):  
O. G. Plyushch ◽  
◽  
V. V. Vyshnivskyi ◽  
S. V. Prokopov ◽  
S. M. Ishcheryakov
Keyword(s):  
Computer Simulation ◽  
Information Systems ◽  
Information Transmission ◽  
Internal Noise ◽  
Telecommunication Networks ◽  
Practical Implementation ◽  
Improve Performance ◽  
Coding Sequences ◽  
Coding Sequence ◽  
Discrete Values

Problems of securing noise immunity and information transmission concealment in telecommunication networks of information systems are considered. In order to improve performance, it is proposed to use scrambling coding sequences, which spread the spectrum of the bits being transmitted. To synthesize new scrambling coding sequences, tenth degree primitive polynomial is used. Autocorrelation properties of the obtained scrambling coding sequence are studied. Limitations caused by those properties are deduced. In order to establish a possibility of synthesized scrambling coding sequence use in the telecommunication networks data transmission channels, it is carried out computer simulation of the transmission process of the bit set, whose spectrum is spread by the obtained sequence. In the process of computer simulation, a mixture of the desired signal in the form of a scrambled bit set, internal noise of information transmission channel and interfering signal was formed. While the powers of the internal noise and interfering signal remained constant, power of the bit sequence gradually assumed three discrete values. As a result of the research, it is established that utilization of the synthesized scrambling sequence permits to perform extraction of the bits being transmitted, under conditions in which the power of the noise interfering signal and the internal noise of the channel surpasses power of the desired channel by up to 18 decibel. The limitations set by the use of the synthesized coding sequence are described. An inference concerning a possibility of obtained coding sequence use in practical implementation of telecommunication channels of information networks is made.

Studying noise immunity of radio information transmission systems with noise-like phase-shift keyed signals and synchronization delay errors

2019 ◽  
pp. 105-113
Author(s):  
G. N. Maltsev ◽  
A. V. Evteev
Keyword(s):  
Phase Shift ◽  
Information Transmission ◽  
Noise Immunity ◽  
Tracking System ◽  
Tracking Error ◽  
Information Symbol ◽  
Transmission Systems ◽  
Synchronization System ◽  
Correlation Receiver ◽  
Selection Of

Introduction: Radio information transmission systems with noise-like phase-shift keyed signals based on pseudo-random sequences have potential noise immunity provided by accurately tracking the delay of the received signal in the correlation receiver. When working with moving objects, the delay of the received signal varies continuously, and the reception quality for noise-like phase-shifted signals highly depends on the synchronization system operation and on the accuracy of estimating the received signal delay by the tracking system. To ensure the required signal reception quality, it is necessary to provide an informed choice of tracking system parameters, taking into account their effects, which are the random and systematic components of the delay tracking error, on the selected noise immunity indicator.Purpose: Analyzing how the errors in tracking the delay of a received phase-shift keyed signal based on a pseudorandom sequence by the synchronization system of a radio information transmission system can affect the probability of erroneous reception of an information symbol.Results: The calculation method was used to obtain families of dependencies of the probability of erroneous reception of an information symbol on the signal-noise ratio (SNR), and the values of the random and systematic components of the delay tracking error which are normalized to the capture band of the correlation receiver. It has been shown that at a fixed SNR, the values of the random and systematic components of the delay tracking error are critical for the erroneous reception probability. In all the cases discussed, all the dependencies are characterized by a slow change of the erroneous reception probability while the synchronization errors within the area of small SNR have fixed values. As the SNR value grows, the erroneous reception probability rapidly drops. To ensure the specified signal reception quality and the reliability of the selection of information symbols and messages in a radio information transmission system with noise-like phase-manipulated signals, its synchronization system requires a joint selection of the tracking system parameters, taking into account the limitations imposed by the operating conditions and technical implementation features.Practical relevance: The obtained results can be used in noise immunity analysis of radio information transmission systems with noise-like phase-shift keyed signals in a wide range of communication conditions, and in providing technical solutions for synchronization systems ensuring the required quality of signal reception.

scholarly journals The unique coding sequence ofpmoCABoperon from type Ia methanotrophs simultaneously optimizes transcription and translation

2019 ◽  
Author(s):  
Juan C. Villada ◽  
Maria F. Duran ◽  
Patrick K. H. Lee
Keyword(s):  
Methane Oxidation ◽  
Meta Analysis ◽  
Nucleotide Composition ◽  
Global Scale ◽  
Translation Efficiency ◽  
Coding Sequences ◽  
Coding Sequence ◽  
Conserved Sequence ◽  
Type Ia ◽  
Optimal Resource

Understanding the interplay between genotype and phenotype is a fundamental goal of functional genomics. Methane oxidation is a microbial phenotype with global-scale significance as part of the carbon biogeochemical cycle, and is a sink for greenhouse gas. Microorganisms that oxidize methane (methanotrophs) are taxonomically diverse and widespread around the globe. Recent reports have suggested that type Ia methanotrophs are the most prevalent methane-oxidizing bacteria in different environments. In methanotrophic bacteria, complete methane oxidation is encoded in four operons (pmoCAB, mmoXYZBCD, mxaFI, andxoxF), but how evolution has shaped these genes to execute methane oxidation remains poorly understood. Here, we used a genomic meta-analysis to investigate the coding sequences that encode methane oxidation. By analyzing isolate and metagenome-assembled genomes from phylogenetically and geographically diverse sources, we detected an anomalous nucleotide composition bias in the coding sequences of particulate methane monooxygenase genes (pmoCAB) from type Ia methanotrophs around the globe. We found that this was a highly conserved sequence that optimizes codon usage in order to maximize translation efficiency and accuracy, while minimizing the synthesis cost of transcripts and proteins. We show that among the seven types of methanotrophs, only type Ia methanotrophs possess a unique coding sequence of thepmoCABoperon that is under positive selection for optimal resource allocation and efficient synthesis of transcripts and proteins in environmental counter gradients with high oxygen and low methane concentrations. This adaptive trait possibly enables type Ia methanotrophs to respond robustly to fluctuating methane availability and explains their global prevalence.

scholarly journals Integral indicator of adjustment parameters estimation of adaptive antenna arrays for telecommunication networks of information systems

Connectivity ◽  
2020 ◽  
Vol 146 (4) ◽  
Author(s):  
O. G. Plyushch ◽  
◽  
V. V. Vyshnivskyi ◽  
S. V. Tolyupa ◽  
S. V. Prokopov ◽  
...  
Keyword(s):  
Computer Simulation ◽  
Information Systems ◽  
Antenna Arrays ◽  
Correlation Matrix ◽  
Parameters Estimation ◽  
Telecommunication Networks ◽  
Transient Processes ◽  
Adaptive Antenna ◽  
Adaptive Antenna Arrays ◽  
Integral Indicator

Adjustment speed is one of the main operation features of adaptive antenna arrays with the steepest descent gradient algorithm in telecommunication networks of information systems. Traditionally, estimation of the transient processes involves a computer simulation of the adaptive antenna array according to the selected noise environment. Substantial time required to create a respective model, big computational load that leads to quite a long period of time for performing required mathematical operations, as well as limited possibilities of simulation results interpretations are among the main drawbacks of the traditional approach. The paper proposes an integral indicator of adjustment parameters estimation of adaptive antenna arrays optimized according to the root-mean-square criterion and that does not require performing of the time consuming computer simulation of the transient processes. Integral indicator assumes values from 1, which corresponds to the quickest adaptation process, to 0, which indicates an absence of adaptation, and is built with account of the eigenvalues distribution of the array correlation matrix, squares of direction cosines of the optimal weight vector on the eigenvalues of the antenna array correlation matrix and the trace of this matrix. Computer simulation helped to establish that the designed indicator permits to correctly predict the speed of the transient processes in adaptive antenna arrays and perform their comparative analysis for different noise environments. Additionally, computation data, which are used for obtaining this indicator, allow us to clearly explain the character of the transient processes in the adaptive antenna arrays.

Simulation of Information Transmission System for Seafloor Observation Platform

2014 ◽  
Vol 701-702 ◽  
pp. 1033-1036 ◽  
Author(s):  
Xi Chen Wang ◽  
Xue Jun Zhou ◽  
Ming Jie Li
Keyword(s):  
Information Transmission ◽  
Chromatic Dispersion ◽  
Optical Network ◽  
Nonlinear Effects ◽  
Transmission System ◽  
Seafloor Observation ◽  
All Optical ◽  
Mutual Independence ◽  
Transmission Quality ◽  
Bidirectional Transmission

This paper presents a scheme of information transmission system for undersea observation platform based on all-optical network. Through flexible using of WDM, OADM, EDFA, RFA, DCF and other technology, it effectively compensates chromatic dispersion, restrains nonlinear effects and noise problems. Fibers in primary nodes are directly assigned to ensure mutual independence between different transmission links. Dual-fiber bidirectional transmission mode that wavelength of one fiber drops to the node by OADM, then return to the same transmission station in the other fiber, increases the reliability of the transmission system. The simulation results show that this scheme can ensure information transmission quality and effectively achieve wavelength adding and dropping, further verify the feasibility of the scheme.

scholarly journals Performance Study of Spread Spectrum Systems with Hard Limiters

2020 ◽  
Vol 12 (5) ◽  
pp. 1-15
Author(s):  
Oleksandr Pliushch ◽  
◽  
Viktor Vyshnivskyi ◽  
Volodymyr Tolubko ◽  
Vadym Mukhin ◽  
...  
Keyword(s):  
Information Transmission ◽  
Spread Spectrum ◽  
Information Transfer ◽  
Dynamic Range ◽  
Internal Noise ◽  
Telecommunication Networks ◽  
Performance Study ◽  
Interference Immunity ◽  
Primitive Polynomials ◽  
Spread Spectrum Systems

Use of spread spectrum systems in telecommunications is studied. It is shown that spread spectrum techniques can substantially enhance noise and interference immunity in the currently deployed information transmission networks. Primitive polynomials are proposed to obtain respective spreading codes. A spreading code consisting of 1023 chips is synthesized and its characteristics are studied. It is deduced that powerful interferences can exceed dynamic range of the receiving part of the system and, as a result, deteriorate information transmission. To overcome this problem, utilization of limiters is proposed, in which limitation level equals that of the internal noise of the receiving part. Computer simulation is employed to test the performance of the proposed solution. Performance of the spread spectrum system for information transfer is studied both without the limiter and with the limiter. Research results show that, for binary modulation, performance of the system with limitation and without limitation is nearly identical while limiters can substantially reduce requirements for the dynamic range. Compared to the existing approaches, it is proposed to use the synthesized spreading coding sequence with the limitation technique in practical implementations of those telecommunication networks, in which noise immunity and transmission concealment are required, such as in unmanned aerial vehicles. This can replace currently used approaches, such as frequency hopping, transmission power adjustment and antenna pattern changes.

scholarly journals Increasing data transmission quality indicators under the influence of the "information aging"

2014 ◽  
Vol 5 (9(71)) ◽  
pp. 51
Author(s):  
Николай Васильевич Захарченко ◽  
Матин Магсуд-оглы Гаджиев ◽  
Владимир Викторович Корчинский ◽  
Александр Николаевич Рябуха
Keyword(s):  
Quality Indicators ◽  
Data Transmission ◽  
Transmission Quality
Sign in / Sign up

Export Citation Format

Share Document