T-Comm最新文献

{"title":"THE MAIN APPROACHES TO EVALUATING THE EFFECTIVENESS OF APPLYING THE RISK ANALYSIS AND MANAGEMENT METHODOLOGY AT ENERGY COMPANY","authors":"Rahmani Jahed","doi":"10.36724/2072-8735-2022-16-9-46-55","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-9-46-55","url":null,"abstract":"At present, it is difficult to imagine the provision of any global services without the introduction of information and communication technologies. The energy company of the Islamic Republic of Iran is territorially distributed, and without a corporate information and telecommunications network, it would cease to exist. In a geographically distributed company on 1,648,195 sq.km, there are several hundred access points and several thousand users of the corporate information and telecommunications network and, therefore, it is very important to understand the possible risks, their assessment and management. In such large geographically distributed corporate information and telecommunications networks with high load, for the use of big data, you need to have a complete picture of risks in order to develop risk models. Without a picture of possible risks, it is impossible to build scenarios for various negative and emergency situations. If we consider the probability of a negative event occurring in the corporate information and telecommunications network as a risk, then its definition, analysis and taking measures to minimize the negative consequences is called risk management. One of the main properties of the risks of a corporate information and telecommunications network is their uncertainty. A geographically distributed corporate network is highly exposed to external factors that can directly affect the quality of its functioning. The occurrence of such situations is difficult to predict.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132319987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiosensor identification and authentication of radio-electronic devices","authors":"K. A. Boikov","doi":"10.36724/2072-8735-2022-16-5-15-20","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-5-15-20","url":null,"abstract":"The presented work is devoted to the study of a new physically unclonable function (PUF) associated with the intrinsic electromagnetic radiation of a radio electronic device. This PUF arises as a result of the technological spread of the parameters of electronic components. The relevance of this study is explained by the fact that modern methods of protecting radio-electronic products from illegal cloning have a number of serious drawbacks associated with increased power consumption, the use of processor time, and the need for galvanic access to the object of study. Partially, these problems are eliminated by PUF, which allow authentication of a radio-electronic device. However, this kind of protection also has serious vulnerabilities in the case of illegal overproduction of products in excess of the ordered quantity. In addition, the PUF does not allow for the identification of radio-electronic products. The purpose of this work is to increase the protection of radio electronic devices from illegal cloning, by studying a new PUF. The work uses experimental research methods to record the electrical component of the electromagnetic field emitted by the product - the signal radio profile (SRP). Correlation analysis methods for product authentication, Pearson's statistical agreement method for identification. SRPs registered from specially designed experimental samples are presented, a correlation analysis of SRP data is carried out. To decompose and extract the parameters of the SRP, its time-frequency spectrum was constructed. A correspondence table was compiled and an analysis of Pearson's agreement was carried out. The results obtained showed the possibility of using the SRP as a new physically unclonable function that allows the identification of radio electronic devices with a probability specified by the researcher, which determines the novelty of the work. It has been established that with Pearson's coefficient of agreement between the parameters of the studied SRP and the benchmark of more than 0.95, a radio-electronic device can be reliably identified. The practical significance of the work lies in the possibility of using the SRP to identify a group of devices and radio-technical protection of a radio-electronic product from fakes and illegal copies.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130220183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INTERMODULATION DISTORTION IN VOLTAGE MODE CLASS D SWITCHING AMPLIFIERS WITH RESISTIVE LOAD","authors":"O. Varlamov","doi":"10.36724/2072-8735-2022-16-10-4-11","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-10-4-11","url":null,"abstract":"The development of 5G technologies and the Internet of Things lead to a change in the traditional paradigm of frequency-territorial planning. Indeed, in addition to reducing the distance between base stations of cellular communication, there is a problem of approaching the radio means of mobile devices to them, as well as the problem of uncontrolled convergence of an arbitrary number of radio means on mobile devices. In all cases, intermodulation distortion (name in English technical literature: reverse intermodulation distortion - RIMD) occurs between closely spaced simultaneously operating transmitters. Once in the reception band, they disrupt the normal functioning of radio equipment. Therefore, the requirements for the transmitter's electromagnetic compatibility characteristics are continuously tightened. Class D power amplifiers, in addition to higher efficiency and better quality indicators, may potentially have a lower level of intermodulation distortion. The article deals with intermodulation distortion in previously unexplored class D push-pull voltage switching mode power amplifier with a resistive load. On the developed theoretical approach basis, an analysis was made of the intermodulation distortion levels dependence on the electronic components parameters spread and the circuit operating mode. It is shown that in order to achieve the desired levels of intermodulation distortion, not exceeding -70 dB, it is necessary to ensure the difference in the active elements saturation resistances is not more than 20% and the saturation time deviation from the meander is not more than 2 degrees.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129293432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NOMA schemes with symbol level processing","authors":"M. Bakulin, T. B. Ben Rejeb, V. Kreyndelin, D. Pankratov, A. Smirnov","doi":"10.36724/2072-8735-2022-16-5-4-14","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-5-4-14","url":null,"abstract":"Requirements for KPI in 6G networks are significantly higher than in 5G networks. Non-orthogonal multiple access (NOMA) technology has been proposed as a solution to meet the requirements of future communication networks. NOMA technology aims to improve the spectral efficiency of wireless communication systems and support the simultaneous operation of large number of subscribers (especially in mMTC scenarios) and provide flexible resource use. This article discusses the popular symbol-level processing NOMA schemes recently proposed as part of the 3GPP standardization, such as SCMA, PDMA, WSMA, MUSA, and other varieties of NOMA. The main advantages and principles of non-orthogonal access technology are illustrated using the NOMA system with division in power domain (PD-NOMA) for uplink and downlink. Characteristics of various symbol-level processing NOMA schemes, their advantages and disadvantages, as well as problems in the way of their implementation in future wireless networks are analyzed. In addition, this article discusses block diagrams of NOMA systems and mathematical models illustrating the formation of baseband signals in such systems. In conclusion, the noise immunity characteristics of the most popular NOMA schemes with symbol-level processing are given for various loading factors. From the analysis performed, it follows that no NOMA scheme has yet been proposed that is effective in various scenarios of future wireless communication systems and has an acceptable processing complexity in combination with flexible resource allocation for mass connection of subscriber devices.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125412900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generalized model of actions by an attacker when manipulating messages containing precise time signals","authors":"A. Kanaev, E. Oparin, E. Oparina","doi":"10.36724/2072-8735-2022-16-6-31-37","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-6-31-37","url":null,"abstract":"This article gives the place and role of the common time system in the telecommunications system, gives an overview of the process of functioning of the common time system, indicating the main means of transmitting accurate time signals. Based on the analysis of the process of functioning of the common time system, the main risks of failures in technological and automated systems in case of violation of the accuracy of the transmission of common time signals are identified. As a result of the analysis of emerging risks, attention is focused on the main types of threats to the single time system when attacks are carried out by organized malefactors. A special place among the threats is occupied by the manipulation of messages containing precise time signals. To analyze this threat, a semi-Markov model of an attacker's actions when manipulating messages containing precise time signals is formed. The main stages of the process of carrying out the attack are singled out. Using the method of minors, the main stationary characteristics of the attack process are calculated, such as the probability of finding the attack process at various stages of its implementation, as well as the average time of the attack duration and the average recovery time of the unified time system from the consequences of the attack. This information also serves as the basis for determining the coefficient of correct operation of the unified time system. The results obtained can be reflected in the formation of strategies for protecting the unified time system from attacks by organized intruders.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125444599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BUILDING A QUALITY ASSESSMENT CRITERION BINARY BARKER-LIKE CODES","authors":"A. Gavrishev, D. L. Osipov","doi":"10.36724/2072-8735-2022-16-12-11-16","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-12-11-16","url":null,"abstract":"The objective of this article is to construct a criterion for evaluating the quality of binary Barker-like codes. The analysis of well-known studies on the formation of these codes with properties close to binary Barker codes is carried out. The analysis showed that in the works devoted to the use of well-known binary Barker-like codes in secure wireless communication systems and the formation of such codes, researchers primarily pay attention to such quality assessment indicators as the autocorrelation function, the length and number of such codes, and others. Based on the analysis of works [5, 9-25], the initial tuple of quality assessment of binary Barker-like codes is formulated, represented by the expression (1). However, the original tuple (1) lacks such an important quality assessment indicator as the linear complexity assessment, which is often taken as one of the primary indicators of crypto resistance. Based on this, the purpose of this article is to increase the accuracy of the evaluation of binary Barker-like codes by applying the identified criterion. The authors of the article, using the Berlekamp-Massey algorithm, evaluated the linear complexity of binary Barker-like codes presented in [9-23]. It has been established that a sufficiently large number of such codes (from 24% to 75%) have insufficient linear complexity, that is, they are non-cryptographic. As a result, they cannot be used in secure wireless communication systems. The result obtained is consistent with other studies in this field. Proceeding from this, when using well-known binary Barker-like codes in secure wireless communication systems, as well as when forming new binary Barker-like codes, it is necessary to pay attention not only to the known quality assessment indicators, but also to their linear complexity. The authors have modified the original tuple represented by expression (1). The modified tuple is represented by expression (2). According to the authors, the modified quality assessment criterion will improve the accuracy of the evaluation of binary Barker-like codes.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126655252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Capacity pre-allocation based on a traffic prediction for latency reduction in geo satellite communication systems","authors":"Sergei S. Averianov, A. Dvorkovich","doi":"10.36724/2072-8735-2022-16-4-46-51","DOIUrl":"https://doi.org/10.36724/2072-8735-2022-16-4-46-51","url":null,"abstract":"Low latency is an important indicator for satellite communication systems on geo earth orbits (GEO). Transmission delay in packet networks includes access delay, propagation delay, and processing delay. The processing delay depends on the performance of the processing methods and system overload management, which is just a small fraction of the total transmission delay at low traffic load. This article dis-cusses the latency of a terminal accessing a network after a connection break. The paper proposes the scheme for maintenance a user terminal synchronization in a satellite communication net-work with bandwidth pre-assignment. The scheme is based on a traffic prediction and not requires a request from the terminal. The place of the proposed scheme in the synchronization maintenance system of the DVB-RCS2 standard is defined. A comparison of the performance of predictive traffic models is given. The latency reduction and the signal-to-noise ratio operating range extension of a user terminal from the use of the proposed scheme for maintaining synchronization is presented. The paper also presents an overview of the application of data analysis methods in the tasks of the time-frequency resource allocation in a GEO satellite communication system.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114077116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE DEPENDENCE OF THE ELECTRODYNAMIC CHARACTERISTICS OF THE MICROSTRIP PHASED ARRAY SUBARRAY ON THE METHOD OF POWER SUPPLY","authors":"E. V. Ukhanov, R. V. Terekhin, Sofia R. Kosichkina, Konstantin V. Strygin, Ekaterina V. Syukieva","doi":"10.36724/2072-8735-2021-15-4-57-64","DOIUrl":"https://doi.org/10.36724/2072-8735-2021-15-4-57-64","url":null,"abstract":"Microwave technology in microstrip design is widely used in various antenna systems. The active use of phased array (PA) of this type makes developers around the world search for various options of its construction. To improve individual characteristics, in particular, expand the scanning angle, as well as optimize the configuration of the excitation of the PA, they use subarrays that combine a given number of elements of the entire array. In this paper, we considered various options for constructing microstrip PA subarrays made on a homogeneous substrate from a high-frequency laminate GIL_GML 1000, in particular, various methods for their excitation. Using modern, accurate 3D electrodynamic modeling environment and HF device analysis, we studied changes in the electrodynamic characteristics of the simulation model of a multi-element microstrip PA subarray, depending on how the excitation is organized. This article discusses three simulation models of subarrays for microstrip PA with various options for their excitation. All subarrays have a radiation pattern of a special shape. After calculating the main characteristics, the issue of the most preferred organization of subarray power supply for the developed PA was solved. It is shown that in practice, the study of parameters and decision-making on the design of complex microwave devices, possibly without expensive field modeling.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128054844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE OPTIMIZATION OF PLACING ELECTRONIC COMPONENTS BY A MODIFIED ALTERNATING-VARIABLE DESCENT METHOD","authors":"T. Harutyunyan","doi":"10.36724/2072-8735-2021-15-3-59-63","DOIUrl":"https://doi.org/10.36724/2072-8735-2021-15-3-59-63","url":null,"abstract":"The problem of optimal placement of elements of electrical and electronic circuits is considered. The minimum weighted connection length is selected as the criterion. A computational method is proposed that is a modification of the coordinate descent method and one of the variants of the General approach based on pair permutations. The scheme is defined by the connection matrix. We consider a fixed set of element positions and a distance matrix based on an orthogonal metric. This problem is a variant of the General mathematical model, called the quadratic assignment problem. Geometric restriction of the problem – no more than one element can be placed in one cell. It is stated that approaches based on paired and similar permutations are economical, and the method of the penalty function leads to” ditching ” and is ineffective. A modified coordinate descent method is described, which is a variant of the pair permutation method, in which pairs are selected based on the coordinate descent method. In the proposed version of the coordinate descent method, two coordinates are changed simultaneously at one stage of calculations (and not one, as in the usual optimization method). one of the coordinates is used for the usual trial step, and the other is used for correction, returning to the acceptable area. Next, the value of the target function is calculated at the found point and compared with the previously reached value. If the value has improved, the found point becomes the new starting point. Otherwise, a step is made on a different coordinate with simultaneous correction of the vector of item position numbers (return to the allowed area). The experience of using the modified method in solving the problem of placing EVA elements has shown its significant advantages in comparison with other known methods, for example, the genetic algorithm, as well as the method of penalty functions. An example of calculations using the proposed method is considered. The connection matrix was set analytically. First, the initial approximation was searched by the Monte Carlo method (10,000 iterations), after which the local optimum was calculated using a modified method of coordinate descent in the permutation space without repetitions (a limit of 100 iterations was set). The initial value of the coordinate step is equal to the size of the permutation, then at each iteration it was reduced by 1 to the minimum possible value of 1. The advantage of this method is that there is no penalty function. The search is performed automatically in the permutation space without repetitions. Computational experiments have shown high computational qualities of the proposed method.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128139313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Algorithm for evaluating the directional characteristics of an antenna array with electric scanning in the observation coordinate system","authors":"N.V. Shatskiy","doi":"10.36724/2072-8735-2021-15-10-4-10","DOIUrl":"https://doi.org/10.36724/2072-8735-2021-15-10-4-10","url":null,"abstract":"An algorithm is proposed for estimating the parameters of the antenna array radiation pattern with electric scanning in the observation coordinate system associated with the phasing direction of the antenna elements. It is shown that in this coordinate system, the concentration of coordinate lines near the phasing direction is maximal. This allows for a relatively small number of observation points to study in detail the parameters of the main beam and the first side lobes of the antenna array, as well as to evaluate the coefficient directivity. The simplest quadrature formula is acceptable for calculating the coefficient directivity in the selected observation coordinate system. The relations for calculating the antenna array radiation pattern taking into account the direction of the beam departures are given. It is shown that taking into account the directivity of individual elements during scanning leads to beam departures, which are convenient to track in the observation coordinate system. Procedures are proposed for estimating the beam width based on linear interpolation of sections of the radiation pattern where the level -3dB intersects. A procedure for estimating the level of side lobes is proposed, which does not include a procedure for searching the area of side lobes. The relations that establish the relationship between the observation coordinate system and the coordinate systems used in radar are given. The results of numerical studies that demonstrate the possibility of visualizing the radiation pattern and its cross-sections in the local coordinate system of the radar system, in the antenna coordinate system, and in the observation coordinate system are presented. This article is the first in a line of research in terms of determining the scientific and methodological apparatus for constructing adaptive algorithms for the diagram-forming scheme of the digital antenna array of radar stations and helps to determine the potential achievable characteristics of newly developed radar stations.","PeriodicalId":263691,"journal":{"name":"T-Comm","volume":"169 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133244810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}