Methodology for assessing the noise immunity of data exchange radio lines with time division of channels

Abstract The very high frequency data exchange system (VDES) is promising in promoting electronic navigation (E-navigation) and improving navigation safety. The multiple access control (MAC) protocol is crucial to the transmission performance of VDES. The self-organising time division multiple access (SOTDMA) protocol, as the only access mode given by current recommendations, leads to a high rate of transmission collisions in the traditional automatic identification system (AIS), especially with heavy traffic loads. This paper proposes a novel feedback based time division multiple access (FBTDMA) protocol to address the problems caused by SOTDMA, such that collision of transmissions can be avoided in information transmission among vessels. Simulation results demonstrate that the proposed FBTDMA outperforms the traditional SOTDMA in terms of channel utilisation and throughput, and significantly reduces the transmission collision rate. The study is expected to provide insights into VDES standardisation and E-navigation modernisation.

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INCREASED NOISE IMMUNITY COMMAND RADIO LINK SIGNALS WITH OFDM

RADIO COMMUNICATION TECHNOLOGY ◽

10.33286/2075-8693-2021-49-07-20 ◽

2021 ◽

pp. 7-20

Author(s):

A. V. Leushin

Keyword(s):

Noise Immunity ◽

Relative Phase ◽

Radio Link ◽

Control Line ◽

Radio Lines ◽

Ability To Work ◽

Signal Noise ◽

Ofdm Signals

Reviewed the work of the command radio link with OFDM signals, which implements a quasicorrelative reception phaseshift keyed signals without a timing that provides improved immunity system and the ability to work in low relations signal/noise at low requirements to stabilize the frequencies of the reference oscillators of transmitter and receiver. The noise immunity estimation of the proposed system in comparison with radio lines operating with signals of frequency telegraphy and relative phase telegraphy is given. The main problematic issues of building a command radio control line caused by the use of OFDM signals are revealed.

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Joint use of frequency-time division and antinoise coding in radio communication systems with FHSS

Российский технологический журнал ◽

10.32362/2500-316x-2021-9-4-77-84 ◽

2021 ◽

Vol 9 (4) ◽

pp. 77-84

Author(s):

A. A. Paramonov ◽

Van Zung Hoang

Keyword(s):

Data Transmission ◽

Communication Systems ◽

Error Probability ◽

Noise Immunity ◽

Signal To Noise Ratio ◽

Frequency Division ◽

Radio Communication ◽

Signal To Noise ◽

Noise Ratio ◽

Time Division

In the context of continuous improvement of radio prospecting and active radio jamming technics along with introduction of automated active countermeasures systems (ACS), the frequency-hopping spread spectrum (FHSS) radio communication systems (RCS) are widely used in order to improve reliability and noise immunity of data transmission. The noise immunity of the RCS affected by unintentional or deliberate interference can be significantly perfected by the combined use of frequency-time division and antinoise coding. This paper explores the case when the interference created by an ACS system with a limited transmitter power covers a part of the RCS frequency range. The receiver gets input mix of the wanted signal, the receiver noise, and probably a deliberate interference also considered as a noise. The article analyzes the noise immunity of signals reception with FHSS in the low-speed radio systems with joint use of frequency-time division of information subsymbols and noise combating codes when the deliberate interference destructively impacts a part of the RCS working band. Dependence of the bit error probability on the signal-to-noise ratio is calculated for the joint use of frequency division of information subsymbols and noise combating codes. It is shown that due to effective use of the frequency-energy resource of a radio line, considering the use of correction codes, a quite high noise immunity of RCS under the influence of deliberate interference can be assured. The indicated dependences of the error probability on the signal-to-noise ratio confirm that the reliability of data transmission can be significantly increased by the proper combination of signal spectrum spreading, applying of correction codes, and frequency division of subsymbols followed by their weight processing.

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Концептуальні основи методики кодування і збереження частотної інформації для перенастроювання радіостанції Р-828 на нові радіодані

Aerospace technic and technology ◽

10.32620/aktt.2021.2.10 ◽

2021 ◽

pp. 84-91

Author(s):

Андрій Олександрович Красноруцький ◽

Алі Енверович Бекіров ◽

Василь В’ячеславович Корепанов ◽

Олександр Анатолійович Хіжнюк

Keyword(s):

Information Content ◽

Data Exchange ◽

Noise Immunity ◽

Radio Station ◽

Storage Device ◽

Labor Costs ◽

Special Equipment ◽

Radio Data ◽

Frequency Information ◽

New Radio

The article describes an innovative approach to encoding and storing frequency information of the R-828 radio station, which is implemented on special equipment of the manned complex. The purpose of the article: to develop a methodology for encoding and storing frequency information according to the сascaded concept for reconfiguring the R-828 radio station to a new radio data. The technology is developed and the methodology for automatic evaluation of current and subsequent radio data according to the cascaded concept for the presence of given information content is revealed. The stages of conversion and encoding frequency radio data of the radio station's storage device using the technology of identifying key features of given information content in the system for entering new radio data are justified. A software implementation of automating the process of converting frequency radio data into a code sequence is proposed. Automation of the recalculation process, which is built in the program for working with Microsoft Office Excel spreadsheets, is justified. The implementation of the method of converting frequency radio data into a sequence code combination is proposed to be implemented using the functions IF, MOD, ROUND, AND. It is proved that to create calculations and document the information component, the Excel table processor is programmatically used, which allows, for further data analysis (if necessary), to automatically create and receive reports in the form of tables and graphs. A method for evaluating the effectiveness of the proposed technology of encoding and storing frequency information of the R-828 radio station on new radio channels is proposed, and the obtained expert results of this method are presented. An experimental assessment of the effectiveness of the developed technology is given, which allows us to assert a reduction in the labor costs for the personnel of the aviation engineering service in the aviation brigades Air Force of the Armed Forces of Ukraine to recalculate frequencies in the appropriate code combinations and to work out control sheets for changing the frequencies of radio station R-828 channels, as well as a reduction in errors of the first and second kind when performing work on changing frequency radio data, by reducing the influence of the human factor on the occurrence of errors when performing appropriate recalculations. The relevance of the problem under consideration is primarily related to the specifics of performing tasks of the aviation engineering service in the conditions of the Joint Forces Operation in the east of Ukraine, namely, an increase in the number of operations to change operating frequencies, which reduces the probability of listening to communication channels by the enemy, which in turn affects the provision an appropriate level of noise immunity and the noise immunity of radio data exchange channels.

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Research of parameters and calculation of the budget of the radio line in the ground-based system of near navigation on the basis of pseudo-satellites

Spacecrafts & Technologies ◽

10.26732/2618-7957-2019-2-101-106 ◽

2019 ◽

pp. 101-106

Author(s):

R. B. Kovalyov ◽

V. N. Ratushnyak ◽

P. Yu. Zverev

Keyword(s):

Navigation System ◽

Noise Immunity ◽

Navigation Systems ◽

Radio Lines ◽

Directional Diagram ◽

Energy Characteristics ◽

Satellite Systems ◽

Radio Line ◽

Navigation Signals ◽

Navigation Information

At present time the most of the work of specialists in the field of navigation is to improve the parameters of navigation systems such as noise immunity and accuracy. At all the world is more and more actual the interest of consumers of high-precision navigation information and equipment manufacturers to near navigation systems, which are an addition to the existing satellite radio navigation systems, allowing them to increase their accuracy and noise immunity. Assessment the parameters is made in the article and algorithm for calculating the radio line in the near-navigation system based on pseudosatellites is generalized. A model for calculating the energy of a radio line has been developed for various configurations of the location of pseudosatellites. The developed program for calculating the characteristics of radio lines of a near-navigation system based on pseudo-satellites allows to quickly evaluate not only its energy characteristics, but also realizes pictorial visualization of the resulting directional diagram of pseudo-satellite systems in accordance with the configured navigation zone of consumers and the required power of navigation signals in natural radio routes.

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Application of permutation frequency modulation signals manipulated with a constant weight code to increase the noise immunity of decameter radio communications

Information and Control Systems ◽

10.31799/1684-8853-2020-6-30-36 ◽

2020 ◽

pp. 30-36

Author(s):

Anton Balykov ◽

Sergey Dvornikov ◽

Sergey Dvornikov

Keyword(s):

Frequency Modulation ◽

Communication Systems ◽

Noise Immunity ◽

Data Transfer ◽

Radio Lines ◽

Radio Communication ◽

Constant Weight ◽

Radio Communications ◽

Decameter Radio ◽

Physical Level

Introduction: The operation of radio lines in the decameter range, as a rule, occurs in a complex interference environment, characterized by the presence of fast and slow fading. Therefore, one of the most relevant areas of research in this subject area is the development of new technical solutions aimed at improving the noise immunity of reception. Purpose: Development of signals with permuted frequency modulation that allow detecting single errors at the physical level by selecting combinations of subcarriers of each character in accordance with the alphabet of the code with a constant weight. Results: Theoretical aspects of formationof the permutation signals with frequency modulation, the choice manipulating code to select subcarriers within a signal symbol, presents an analytical approach for the derivation of the generalized expression evaluation of noise immunity of the developed signals of permutation modulation in a channel with variable parameters in incoherent processing, we obtained the estimation of the values of probability of bit error for new signals in comparison with the known results. Practical relevance: The developed signal with permuted frequency modulation is proposed to be used in decameter radio communication systems operating in a narrow frequency band in the ionospheric channel. Discussion: Further research is associated with optimization of decision-making procedures for demodulating the developed signals, as well as the search for effective ways to encode signals with permuted frequency modulation at the physical level, allowing to increase the data transfer rate while maintaining the noise immunity of reception.

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A study of cometary eruptions through OH radio-lines

International Astronomical Union Colloquium ◽

10.1017/s025292110003150x ◽

1999 ◽

Vol 173 ◽

pp. 249-254

Author(s):

A.M. Silva ◽

R.D. Miró

Keyword(s):

Short Duration ◽

Growth Curves ◽

The Other ◽

Initial Mass ◽

Radio Lines ◽

Other Hand ◽

Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

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Machine-Scored Syntax: Comparison of the CLAN Automatic Scoring Program to Manual Scoring

Language Speech and Hearing Services in Schools ◽

10.1044/2019_lshss-19-00056 ◽

2020 ◽

Vol 51 (2) ◽

pp. 479-493

Author(s):

Jenny A. Roberts ◽

Evelyn P. Altenberg ◽

Madison Hunter

Keyword(s):

Data Exchange ◽

Child Language ◽

Exchange System ◽

Absolute Point ◽

Language Analysis ◽

Search Patterns ◽

Language Data ◽

Report Accuracy ◽

Point To Point ◽

Automatic Scoring

Purpose The results of automatic machine scoring of the Index of Productive Syntax from the Computerized Language ANalysis (CLAN) tools of the Child Language Data Exchange System of TalkBank (MacWhinney, 2000) were compared to manual scoring to determine the accuracy of the machine-scored method. Method Twenty transcripts of 10 children from archival data of the Weismer Corpus from the Child Language Data Exchange System at 30 and 42 months were examined. Measures of absolute point difference and point-to-point accuracy were compared, as well as points erroneously given and missed. Two new measures for evaluating automatic scoring of the Index of Productive Syntax were introduced: Machine Item Accuracy (MIA) and Cascade Failure Rate— these measures further analyze points erroneously given and missed. Differences in total scores, subscale scores, and individual structures were also reported. Results Mean absolute point difference between machine and hand scoring was 3.65, point-to-point agreement was 72.6%, and MIA was 74.9%. There were large differences in subscales, with Noun Phrase and Verb Phrase subscales generally providing greater accuracy and agreement than Question/Negation and Sentence Structures subscales. There were significantly more erroneous than missed items in machine scoring, attributed to problems of mistagging of elements, imprecise search patterns, and other errors. Cascade failure resulted in an average of 4.65 points lost per transcript. Conclusions The CLAN program showed relatively inaccurate outcomes in comparison to manual scoring on both traditional and new measures of accuracy. Recommendations for improvement of the program include accounting for second exemplar violations and applying cascaded credit, among other suggestions. It was proposed that research on machine-scored syntax routinely report accuracy measures detailing erroneous and missed scores, including MIA, so that researchers and clinicians are aware of the limitations of a machine-scoring program. Supplemental Material https://doi.org/10.23641/asha.11984364

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